*ZW1CKER'S* 



2 rUiScD 



MACHINISTS 

'iremen, Electricians 



STEAM ENGINEERS 



b 



ZWICKER'S 

EEVISED. 

PRACTICAL 

INSTRUCTOR 

IN 

Questions and Answers 

FOR 

Machinists, Firemen, Electricians 

AND 

f STEAM ENGINEERS. 

^F ! ' — / 

Philip Henry Zwicker. 

Practical Engineer and Machinist, r 

1607 Wash Street. 

ST. LOUTS, MO. 

1890. 



! <J 



^3 



Entered according to Act of Congress. 

in the year 1890. 

By Philip Henry Z wicker, 

In the office of the Librarian of Congress at Washington. 

Ail rights of Translation reserved. 



fs3 



j/^ 



!/> 






INTRODUCTION. 

This book is written for the 'special information 

of Engineers, Machinists, Firemen and Electri- 
cians who have to sooner or later procure an 
engineers license by going before a board of prac- 
tical engineers and answering questions relating 
to the care of boilers, pumps, injectors, engines, 
indicator safety-valve and electric light dynamo. 
Before they can collect their salary as an engineer. 
It is hoped its practical suggestions will enable 
those who follow them to gain a better insight 
of the work they have to perform. The real 
object in writing this book is io help my fellow 
man and not keep him in the dark. All questions 
are answered in plain and simple language, so any 
man of limited education can thoroughly under- 
stand. 

Very truly yours, 

P. H. Z wicker, Author. 



ZWICKER'S 

REVISED 

PRACTICAL INSTRUCTIONS 

IN 

QUESTIONS AND ANSWERS 



Machinists. Firemen, Electricians and Steam Engineers 

Q. What are the duties of an Engineer? 

A. His duties are to take full charge of the 
boilers and engines where ever he may be employ- 
ed, and see that the steam machinery under his 
charge are kept in No. 1 order with little expense 
to his employer. 

Q. What is required of a man to become a 
first-class Engineer? 

A. He is obliged to obtain an Engineers license 
touching his qualifications as an engineer of steam 
engines, by which will be shown that he is a 
suitable and safe person to be intrusted with tl e 
powers and duties of an engineer. 

Q. What experience must a man have in order 
to get his application before a board of Engineers ? 



(5) 

A. His experience must be generally two years, 
at mechanical or steam engineering, which must 
he sworn to by two citizens, one being a licensed 
engineer and the other a good reliable citizen, 
both living in the city, where applicant has worked- 
QUESTIONS AND ANSWERS. 

Q. What business do you follow? 

A 

Q. What is a steam boiler, how is it, and of 
what is it made ? 

A. A steam boiler is a closed vessel made Of 
steel, iron or copper plates, the most in use is 
f ^ and £ inch thick, and ranging from 45,000 
to 85,000 lbs. tensile strength; these plates are 
run through a rolling machine and rolled in a 
circle, then riveted together, generally with two 
rows of rivets, because the strain is greater side- 
wise than endwise, the seams around the boiler 
are single riveted because the strain is not so 
great; the boiler is braced by different kinds of 
braces, such as a crow foot, Longitudinal dome, 
side braces, etc. The eye is riyeted to the head 
of the boiler, which head is generally made of f 



(6) 

inch plate, the other eye is riveted to the side top 
or dome of boiler, and the brace and eye are put 
together by bolts with a split key to keep the belt 
in its place. 

Q. Which are the chief points in the construc- 
tion of a successful and economical boiler ? 

A. Proper circulation facilities constitute one of 
the chief points in the construction cf a success- 
ful and economical boiler. In tubular boilers, 
the best practise is to place the tubes in vertical 
rows, (plumb) leaving out what would be the 
center row. The circulation is up the sides of 
the boiler and down the center. Tubes set zig- 
zag or to break spaces impede the circulation and 
will not practically give the best results. 

Q. How should a brace fit? 

A. It should fit tight, fcr if it were loose it 
would be of no account. 

Q. If you found a brace loose, what would you 
do, and how would you tighten it 

A, By taking the brace out, heat it in the 
center, then upset it by jumping it endwise on a 
block of wood until it is the proper length. 

Q. Why is a boilei braced ? 



A. For strength. 

Q. What is a stay bolt? 

A. A stay bolt is a screw bolt, put through 
an outside and into an inside sheet, so as to 
hold them that they may not spread or collapse, 
such as a fire-box sheet and an outside shell, 
they are put together with stay bolts so as to 
allow a water space between the two sheets. 

Q. How are stay bolts made and put in? 

A. They are made with one continuous 
thread, and screwed through the outside, then 
through the space between, then through the 
fire-box sheet and allowed to stick through T 3 g- 
of an inch, so they can be riveted over each 
end to act as a brace, the space between the 
two sheets is called a water space. 

Q. What is meant by corrosion? 

A. It means wasting away of the iron of 
boilers plates by pitting, grooving, etc. There 
is internal and external corrosion; the acids in 
and minerals in the water liberated by the heat, 
attack the boiler internally, and the sulphur 
which comes out of the coal has a strong at- 
tachment for iron, and that attacks the outside. 



Q. How would you find the water level 
when your boiler is foaming? 

A. The proper w^ay would be to shut down 
the engine and all valves connected with the 
boiler, cover fire with ashes, close the damper, 
then the water will quiet down, and the level 
of the water easily found. An engineer should 
know when lighting a fresh fire, never to force 
it, but let it heat gradually, so that all parts ex- 
pand as near equal as possible; good judgment 
is needed. Boilers and steam guages should be 
tested at least once a year. 

Q. Where would you put a steam gauge? 

A. Sometimes on top of the boiler, and in 
some cases on the steam drum. It must always 
be tapped into the steam part of the boiler, the 
shorter the pipe the better. The steam gauge 
and safety valve should correspond under all 
circumstances. 

Q. Why is a pet cock put under the steam 
guage? 

A. To drain the pipe in cold weather. 

Q. What kind of a steam gauge have you 
got? A. A spring gauge. 



Q. What is a steam gauge for? 

A. To indicate the pressure in pounds per 
square inch in the boiler. 

Q. Does the steam gauge get out of order? 

A. Yes, sometimes. 

Q. If the steam gauge was out of order what 
would you be governed by? 

A. By the safety valve. 

Q. How would you know that it was in 
working order? 

A. By raising the lever two or three times 
to see that the valve is not stuck. 

Q. What is a safety valve for? 

A. It is intended to release the boiler and 
prevent explosions from over-pressure. 

Q. How large should the safety valve be in 
proportion to the boiler, and grate surface? 

A. The safety valve should be \ square 
inch to each square foot of grate surface, which 
will make it large enough to relieve the boiler 
of all steam generated over which the safety 
valve is set. 

Q. Which are the better, gauge cocks or glass 
gauges, and which would you be governed by? 



— 10 — 

A. Gauge cocks, because glass gauges are 
liable to get stopped with mud, and not give a 
true level of the water, but they are a very 
handy thing; they should be blown out four or 
five times a day, so as to keep them from clog- 
ging up. 

Q. What would you do in case a glass should 
happen to break? 

A. First close the water valve to prevent 
the escape of water, close the steam valve, in- 
sert a new glass, then turn on the steam valve 
first, the water valve next, then close the pet cock 
at the bottom and everything will be all right. 

Q. What is the best way to clean a glass 
gauge inside? 

A. The best way, is to take a small piece of 
waste and tie it to a strong thin stick, saturate 
the waste with soap or acetic acid, pass down 
inside of the glass, then blow through with 
steam and the glass will be clean as new. Never 
touch the inside of a glass water gauge with 
wire, if you do, it will crack. The best glasses 
are the Scotch brand, called Eureka. 

Q. If your gauge cock, or a small pipe in 



— li- 
the large steam pipe, should happen to get 
broken off, what would you do? 

A. Make a hard wood plug and drive it in 
with a heavy hammer, then leave it so until it 
could be repaired, by cutting out the old piece, 
retapping and putting in another pipe or gauge 
cock, whichever the case may be. 

Q. What clearance should a boiler have? 

A. It should have from 3 to 4 inches at the 
fire-line, and from 5 to 7 inches between the shell 
and bridge wall; a boiler should have from 2 
to 3 bridge walls so the fire will hug the boiler; 
it also makes the coal burn cleaner and steams 
easier. The first bridge wall should be on the 
back end of the grate bars, and others about 3 
to 5 feet apart, according to the length of the 
boiler. Where the smoke returns through the 
flues, it should be about ^ larger than the area 
of flues or tubes combined, bridge walls should 
lean toward the back. 

Q. How should a boiler rest and what on? 

A. The front end of the boiler should rest 
on the fire front, and the back end generally 
rests on a cast iron leg or two or three rollers, 



— 12 — 

to allow the boiler to expand equally. The mud 
drum should always hang free under all circum- 
stances, 

Q. In what should engineers be careful and 
exercise good judgment? 

A. Engineers should be careful in starting 
or stopping an engine with a high pressure 
of steam. 

Q, Why should engineers be careful in 
starting or stopping an engine? 

A. Because the rent in giving the steam in 
starting, and the sudden check in stoping, may 
cause such a pressure as to rupture the boiler. 

Q. What else should engineers look after? 

A. Engineers should see that their draft is 
not choked by ashes under the boiler, and that 
the outside of the boiler and inside of flues 
are kept clean, then they will have no trouble 
in keeping up steam. 

Q. How would you clean the flues or tubes 
of a steam boiler? 

A. By either blowing steam through them 
or using a flue cleaning brush. 

Q. How are flues or tubes cleaned by steam? 



— 13 — 

A Some boilers have a 1* inch pipe with a 
va lv'e attached, al,o branch pipes of smaller 

dim ensions, leading from the ti inch p.pemto 
the back end and into the flues; others have 
h ose attached to the front end leading f rom te 
steam drnm, so the flues or tubes can be blown 
ottTromthlfrontend^Cleaningbv the brush 

i8 the better and more popular way.) 

Q. How often would you clean out the 

flues and when? 

A. Once a day, in the afternoon, sometimes 

in the morning after raising steam 

q What different strains bas a boiler . 
A To the flues or tubes it has a crushing 
strain, to the shell a tearing strain. 
q What causes boiler explosions i 
A There are various causes, such as low 
water, over-pressure of steam, bad safety 
valve, foaming boilers and burnt sheets. 

q. Why would a foaming boiler cause an 

'TT generally raises the water from the 
ueat'ed sheets. They become hot; the water 
falling back on them they crack, and some- 



— 14 — 

times cause an explosion. A blistered sheet or 
a scaly boiler will also cause an explosion, by 
allowing the sheets to become burnt and weak 
ened; also an untrue steam gauge is very bad. 
Q. What are the worst explosions? 
A. The worst explosions are caused by high 
pressure and plenty of water; low water allows 
the iron to burn and crack, which weakens it, 
and when the cold water touches it, it does not 
take so much to burst. 

Q. How would you know i f your boiler had 
blistered sheets or was rotten? 

A. By the hammer test; by taking a small 
hammer and going inside and outside of the 
boiler and seeing if it is all right by sound. 
Q. How would you know by sound? 
A. By the different sounds it has; if it rings 
and sounds solid it is all right; but if it sounds 
dead, hollow or blunt, there is something 
wrong. 

Q. Would you strike the iron hard? 
A. Yes, pretty hard. 

Ho not hesitate to have a boiler insured, as 
insurance is generally accompanied by hammer 



— 15 — 

test and intelligent inspection, which guaran- 
tees safety to the engineer or owner. 

Do not reject the advice or suggestions of 
intelligent boiler inspectors, as their experience 
enables them to discriminate in cases which 
never come under the observation of men who 
do not follow inspection as a business. 

Q. If you wished to put a patch on a boiler 
what kind would you put on? 

A. A hard patch; it is reliable and safe. 

Q. Why not put on a soft patch? 

A. Because they are not reliable and are 
dangerous. 

Q. What is the difference between a hard 
and soft patch ? 

A. A hard patch is a patch where the piece 
is cut out of the boiler and rivet holes are 
drilled or punched through, then the- patch is 
riveted on, chipped, caulked and made water 
and steam tight. 

Q. What is a soft patch ? 

A. A soft patch is put ever the plate that 
needs patching, and put on with f or f inch 
countersunk screw bolts, and a mixture of red 



— 16- 
lead and iron borings to put between the patch 
and boiler; the piece of sheet in the boiler is 
not cut out for a soft patch as in a hard patch, 
consequently the patch is burnt, as the water 
in the boiler can not come in contact with the 
patch. 

Q. Which are the better, drilled or punched 
holes ? A. Drilled holes. 

Q. Why ? 

A. Because the fiber of the iron is not dis- 
turbed as in punching ; in drilling, the iron is 
cut out regular; in punching, it is forced out at 
once. 

Q. What should be the proper rivets for 
certain sized sheets, and how far apart ? 

A. The rivets should be § and f inch diam- 
eter, and If to 2 inches apart. 

Q. Before shutting down at night, what 
should be done? 

A. Pull out the fire, pump up to the third 
gauge and close the glass gauge cocks, so that 
in case the glass should happen to get broken 
during the night, the water could not escape. 

Q. What would you do the first thing 



I 



— 17 — 

in the morning on entering the boiler-room. 

A. See how much water was in the boiler 
by trying the gauge cocks, then open the glass 
gauge valves, and start the fire to raise steam. 

Q. Why do you try the gauge cocks, and 
not trust to the glass gauge? 

A. Because the water pipe connecting the 
glass gauge with the boiler is liable to become 
stopped up with mud, consequently the glass 
would not show a true level of water. The 
glass gauge should be blown out five or six 
times a day, to insure safety, but never depend 
on the glass gauge alone. 

Q. If you found too much water in the 
boiler during the day, what would you do? 

A. Open the blow off valve and let out water 
to the second gauge. An engineer should be 
very careful when blowing out water when he 
has a hot fire in the boiler furnace, as the water 
leaves very fast, and may blow out too much ; 
good judgment should be used. 

Q. How would you clean a boiler ? 

A. First see that there is no fire under the 
boiler, then let out all the water through the 



— IS — 

blow-off valve, take out the man, hand, and 
mud-drum plates ; then take a short-handle 
broom, a candle or torch, a small hand-pick, a 
scraper made out of an old file flattened on the 
end and bent to suit, also a half- inch square iron 
twisted link chain, about 3 feet long, with a 
ring at each end to answer for a handle ; place 
the chain around the flue and work the chain to 
get the scale off the bottom of the flues; use the 
pick and scraper to pick and scrape off all that 
can be seen on top of the flues and the bottom 
and sides of the shell ; then wash out into the 
mud-drum; clean out and put in the mud-drum 
and hand-hole plates; fill up to top of flues; then 
put in the man-hole plate, and fill up to the sec- 
ond gauge ready for raising steam. 

Q. Could a boiler not be blown out ? 

A. Yes, but not practically. 

Q. How much pressure would you allow ? 

A. About 10 or 20 pounds. 

Q. Why not more pressure? 

A. Because the heat would be so great that 
the expansion and contraction would not be 
equal ; consequently, the boiler seams would 



— 19 — 

probably leak and the boiler be injured. The 
better way is no steam pressure. 

Q. What benefit is gained by letting the 
water stay in the boiler until you are ready to 
clean it out ? 

A. The mud is kept soft and the scale is not 
caked to the shell or tubes; also, the seams and 
the boiler are not injured by unequal expansion 
and contraction. 

Q. How should man and hand-hold plates be 
taken out and put in? 

A. They should be marked with a chisel at 
che top, also the boiler at man-hole and hand- 
hole, whichever it might be, and they should be 
put in the same way they came out. 

Q. How would you gasket the man-hole or 
hand-hole plates of a boiler ? 

A. With pure lead rings ; some use sheet 
rubber, etc. 

Q. Why are man-hole and hand-hole plates 
made oblong instead of round ? 

A. Because if they were round they could 
not be taken out or put in, and a man could not 
easily enter the boiler. 



— 20 — 

Q. When filling a boiler with cold water, 
and raising steam, what should be done ? 

A. A valve should be left open. 

Q. Why do you leave a valve open ? 

A. Because a boiler fills easier and quicker, 
and in raising steam the cold air is let out, 
which allows equal expansion, as cold air pre- 
vents equal expansion. 

Q. How would you set a boiler? 

A. By using a spirit level across and along 
the flues allowing the end furthest from the 
gauge cocks ^ inch lower for every 10 feet ii 
length. Q. Why ? 

A. Because when there is water in the 
gauge cocks, there will surely be water in the 
other end. 

Q. How many gauge cocks has a boiler? 

A. Generally three. 

Q. Where is the first ? 

A. Two inches above the flues, and the rest 
two inches apart. 

Q. Where is the water line? A. First gauge. 

Q. Where would you carry water when 
running ? A. Second gauge. 



— 21 — 

Q. Where would you carry water when 
shutting down at night? A. Third gauge. 

Q. Why? 

A. To allow for evaporation and leakage. 

Q. Where is the fire line of a boiler ? 

A. In line or little below first gauge. 

Q. When you open a boiler and look in, 
where do the scales form and lay thickest ? 

A. Over the fire-plates and around the mud- 
drum leg or blow-off pipe. 

Q. Why? 

A. Because the circulation and heat are 
greatest there. 

Q. What is a steam drum for? 

A. To have more steam in volume. 

Q. Which is the hotter, coming out of the 
same boiler, steam or water ? 

A. They are the same, only water will re- 
tain the heat longer, as water is a fluid and 
steam a vapor. 

Q. How should the circulation and feed be? 

A. The circulation and feed should be con- 
tinual. Q. Why ? 

A. Because boilers have exploded just as 



— 22 — 

the steam valve was opened to start the engine, 
after having stood still for some time. This is 
generally caused by the plates that are in con- 
tact with the fire becoming overheated, as the 
circulation being stopped after the steam is shut 
off. And just as soon as the valve is opened 
the pressure becomes lessened, and the water on 
the overheated sheets flashes into steam of 
gee at elastic eoece, and if the boiler is not 
strong enough, a terrific explosion is the result. 

Q. If you tried the gauge cocks and found 
no water in sight, what would you do? 

A. Simply shovel wet ashes over the fire 
pull it out, raise the flue caps and let the boiler 
cool down. 

Q. Why do you throw wet ashes over the 
fire before pulling it out? 

A. If the fire was stirred up it would create 
more heat and be liable to burn the plates. 

The braces in the boiler should be examined 
to see if they are loose, also the sheets, flues, 
heads and seams, to see if they are cracked or 
leaking ; if they are not attended to, they may 
cause trouble and loss of life and limb. Engi- 



93 

— £o 

neers should not allow anything about the en- 
gine or boiler room to become greasy or dirty, 
for it shows poor management, and a careless, 
worthless engineer. If valves or cocks leak, 
they should be ground in with emery and oil 
until a seat or true bearing is found. Ground 
glass is good for grinding brass valves. 

Q. When should the boiler seams be 
caulked ? 

A. When the boiler is empty and cold, for 
when the boiler is hot and filled with v> r ater, the 
jarring while caulking would have a tendency 
to spring a leak somewhere else. 

Q. Would you call pressure and weight the 
same? A. No. Q. Why? 

A. Because pressure forces in every direc- 
tion, w T hile weight presses down. 

Q. Which is best, the riveted or the lap- 
welded flues ? 

A. The lap-welded flues, as they are a true 
circle and not so easily collapsed as the riveted 
flues. Q. Why ? 

A. Because the riveted flues are not a true 
circle. 



— 24 — 

Q. What is foaming? 

A. Foaming is the water and steam mixed 
together. 

Q, What causes foaming? 

A. Dirty, greasy, oily and soapy water; salt 
water forced into fresh water, also too much 
water and not enough steam room, will cause 
foaming. 

Q. What is priming? 

A. Priming is the lifting of water with 
steam, such as opening a valve suddenly, and 
drawing the water from the boiler to the cyl- 
inder of the engine. 

Q. What would you do in that case ? 

A. Close the throttle valve and leave it 
closed for a few minutes, then open the valve 
slowly; that will remedy it. Sometimes prim- 
ing is caused by too much water and not enough 
steam room; in that case carry less water. 

Q. Are boilers sometimes injured by the 
hydraulic test? 

A. Yes, if tested by an inexperienced per- 
son. The hydraulic test is the safest, because 
if the boiler is bursted no one is likely to get 



— 25 — 

hurt. Never use steam pressure under any cir- 
cumstances for testing. 

Q. If you had a high pressure of steam, and 
water was out of sight, would you raise the 
safety valve to let off the pressure ? 

A. No, under no circumstances. 

Q. Why not ? 

A. Because it would cause the water to rise, 
and when the valve closed the water would drop 
on the heated parts and be liable to cause an 
explosion. 

Q. If your boiler was too small to keep up 
the amount of steam required, would you 
weight down the safety valve to carry a higher 
pressure? A. No. 

Q. Why not ? 

A. Because it would show carelessness and 
a violation of the laws. There is no mystery 
about boiler explosions. They are simply 
caused by carelessness, and no man has the 
right to endanger the lives and property of 
others when he knows that he is incompetent 
to perform the duty required of him as an engi- 
neer, whether licensed or otherwise. 



— 26 — 

Q. How much space should there be between 
the tubes of a steam boiler? 

A. The space should be one-half the diam- 
eter of the tube itself. 

Q. Can you name the principal valve on a 
steam boiler ? 

A. Yes. The safety valve, by all means. 

Q. Where should the lower gauge cock be 
placed in an upright boiler, any size boiler? 

A. One-third the distance from the top, be 
tween the two flue sheets. 

Q. How long a time would you consider it 
safe to leave the engine room alone without 
attention? 

A. Under no circumstances should the en- 
gine or boiler room be left alone. 

Q. Why not, when everything is in working 
order? A. Because no man can tell at what mo- 
ment an accident might occur, which if neglected 
might cause a serious loss of life and property. 

Q. What is the boiling point of water? 

A. It is 212 degrees of heat. 

Q. At what point does water turn into 
steam ? A. It evaporates at 213 degrees. 



PUMPS. 

Q. What kinds of pumps are there? 

A. There are many kinds, but we consider 
only single action and double action for feeding 
boilers and general use. 

Q. How many valves has a single action 
plunger pump? 

A. Two valves, a receiving valve and a dis- 
charge valve. 

Q. How many valves has a double action? 

A. Four, two receiving and two discharg- 
ing. The double action receives and discharges 
both strokes. This kind of pump has a steam 
cylinder on one end. Large pumps have eight, 
sixteen and thirty-two small valves on water 
cylinder, according to the size of the pump. 

Q. Why do large pumps have many small 
water valves and not a few larger ones in pro- 
portion? 

A. The reason the pumps have small valves 
is that the valves do not have to open as much 
as larger ones, consequently the pump does not 

-27- 



— 28 — 

loose the quantity of water each stroke as it 
would with larger valves. 

Q. How are pumps set up and leveled? 

A. Set the pump so the receiving is from 
the boiler and the discharge toward the boiler, 
put in the same size receiving and discharge 
pipe as tapped in the pump, so the pump can 
have a good supply and discharge. The pump 
is leveled with a spirit-level or a square and 
plumb line. To level a double-action pump, 
some level across the frame and along the pis- 
ton; the other way is to take the valve cham- 
ber cap off the water cylinder and level the 
valve seats, so the valves will rise and drop 
plumb. To level a single action pump, take off 
the valve chamber caps and level both ways. 

Q. How are the steam valves of duplex 
pumps set and adjusted? 

A. Take off the valve chest cover, shove 
the piston against one of the cylinder heads 
and mark the piston rod with a pencil at the 
packing-box gland, then shove the piston 
against the other cylinder-head and make a 
another mark, find the center between the two 



— 29 — 
marks and move the piston until the center mark 
reaches the packing-box gland where the first 
mark was made. Or in other words plumb the 
lever that connects the valve rocker shaft and 
the piston. After this is done, see how the 
steam valve is for lead; if equal at both ends 
the valve is set, if not, adjust by uncoupling 
the valve stem at the coupling outside of the 
packing box, and turn to suit the adjustment in 
equalizing the "lead." 

Q. How is the water piston packed and with 
what in the water cylinder ? 

A. It is generally packed with square canvas 
and rubber mixed packing; it generally takes 
two pieces; one piece is jointed on top, and the 
other at the bottom, to make what engineers 
call a broken joint. The packing runs from \ 
to |- inch square. These are the general sizes 
used for common sized pumps. 

Q. What other valve has a pump near the 
boiler ? 

A. A check valve. 

Q. What is a check valve for? 

A. To check the water in the boiler from 



— 30 — 
coming back, in case there is any work to be 
done on the pump. 

Q. Could you pump water into the boiler 
if you had four or five check valves on the dis- 
charge pipe? A. Yes, I could force throngh 
all, but it would be more labor on the pump, 
because the plunger would have to force harder 
to raise the number of check valves. 

Q. Where is a pet cock put on the pump 
barrel for cold water, and why? 

A. It is put at the side and near the bottom 
of the pump barrel, and is there to show how 
the pump is working, and to drain the pump in 
winter to prevent freezing. 

Q. How do you know when your pump is in 
good working order? 

A. By opening the pet cock and seeing the 
stream that comes out. 

Q. How does it show when the pump is in 
good working order ? 

A. Nothing in the suction stroke and full 
force in the discharge stroke. 

Q. Where would you locate the trouble if it 
came full force both strokes? 



O 1 

A. 1 would locate it at check and discharge 
valves, both being caught up. 

Q. Where would you locate the trouble if 
it came full force both strokes, moderate, tank 
or hydrant pressure? 

A. At the receiving valve. 

Q. Can you run a pump without a check 
valve ? 

A. If the discharge valve is in good order, 
it can; but if there is neither check nor dis- 
charge, it can not. 

Q. Can you feed a boiler without a pump? 

A. If the pressure of the boiler is below the 
pressure of the feed water or city pressure, it 
can, by simply opening a water valve and let- 
ting in the amount of water required. 

Q. What other way is a boiler fed? 

A. By an injector or an inspirator. 

Q. What is an injector or an inspirator? 

A. They are devices to answer for a pump 
in feeding a boiler; they draw force and heat 
the water at the same time. See Page 46. 

Q. Must a pump have a valve? 

A. Yes, if a pump had no valve it would not 



— 32 — 
do any work. A pump is not a pump unless it 
has a valve. There are common well hand 
pumps with one valve, called a receiving or 
suction valve, but a force pump has two valves, 
a receiving and discharge ; the discharge is to 
retain the water after it is delivered, so the 
plunger can get a fresh supply. After the 
plunger has ascended and begins to descend, 
the water sets on top of the receiving and under 
the discharge; consequently, when the plunger 
descends it forces the receiving shut and the 
discharge open. 

Q. Should there not be another valve near 
the boiler ? 

A. Yes, a globe valve between the check 
valve and the boiler. 

Q. What is that for ? 

A* To close and keep the pressure in the 
boiler in case the check valve is caught up 
and needs repairing. 

Q. Can you raise, lift or suck hot water 
with a pump ? A. Not very well. 

Q. Why ? 

A. Because the pump would get steam 



— 33 — 

bound. Hot water should be level o. Higher 
than the pump in order to work well. 

Q. Where should a pet cock be put on the 
pump barrel for hot water ? 

A. At the top of barrel, immediately under 
the packing ring. 

Q. Why is it put there ? 

A. To let out steam when steam bound, 
and air when air bound. There should be a 
pet cock tapped in the cap of the valve 
chamber to let off the steam or air when steam 
or air bound. 

Q. If you had no pet cock on the valve 
chamber cap, what would you do ? 

A. Simply take a wrench and loosen one 
of the nuts a little until the air or steam was 
out, then tighten it again. 

Q. Why is an air chamber put on a double 
action pump, and what is it? 

A. It is simply a copper vessel air tight. 
When the pump is working, the water is 
forced up into the chamber, compresses the air, 
and the air acts as a cushion on the valves and 
piston head in tliQ w&ter cylinder. 



— 34 — 

Q. What is a cushion ? 

A. A cushion is anything that is com- 
pressed, and by its compression is formed into 
a higher and stronger pressure, consequently 
acting as a spring, deadening any knock that 
might have occurred otherwise, as water will 
cause a knock, it being nearly as solid as 
iron, so if a double action pump had no air 
chamber, there would be a continual thump- 
ing noise. Q. What is a vacuum ? 

A. A vacuum is a space void of matter. 

Q. Can a perfect vacuum be formed ? 

A. No, about 9 to 11 per cent, of the atmos- 
phere, which is 14.7 pounds per square inch. 

Q. What will a vacuum do ? 

A. It will lift water 33 feet, providing all 
pipes and connections are air tight. 

Q. How is a vacuum created or made ? 

A. When the plunger of a pump is well 
packed and it lifts, it excludes the air out of 
the pump barrel and suction pipe, conse- 
quently the water, being at the other end of 
the pipe, it follows the plunger; or, in other 
words, the atmospheric pressure, being 14.7 



— 35 — 

pounds per square inch, forces the water up the 
pipe to fill the vacancy made by the plunger 
forming the vacuum. Q. What should be placed 
at the bottom of the suction pipe ? 

A. A strainer made out of gauze wire, a 
foot valve and a pet cock to drain it. 

Q. If your pump should not be working, 
your water running low, and you were asked 
to run a little while longer, would you run and 
let your water become dangerously low ? 

A. No, take no chances whatever, but shut 
down and go about repairing the trouble. 

Q. Where would you look for the trouble ? 

A. Open the pet cock of the pump, and 
that will very nearly tell where to look for it; 
if no water comes out, the water is shut off, or 
there is none, etc. 

Q. What generally prevents a pump from 
working ? 

A. Not enough water, too small a suction 
pipe and obstruction of the valves to seat, by 
straws, sticks or anything that may be drawn 
through the suction pipe, or the pump valves 
becoming hot and sticking. 



— 36 — 

Q. If an accident happened, such as a 
broken pipe connected with the boiler and 
pump, or you could not get sufficient water to 
supply the boiler, what would you do ? 

A. Simply shut down the engine and all 
valves connected with the boiler, draw fire, 
raise flue caps, and close the damper, so as to 
keep what water there is in the boiler until 
the difficulty is repaired. 

Q. If your suction pipe should spring a 
leak, what would you do ? 

A. Take a piece of sheet rubber, some cop 
per wire, wrap around tight, and stop the leak 
temporarily. Q. If your hydrant, that sup- 
plies pump with water, should happen to get 
broken, what would you do ? 

A. First see how much water was in the 
boiler, by trying gauge-cocks, then shut off the 
water in the street, or wherever the lazy cock 
lay, and try to wrap it, if possible, or repair it. 
If an injector or inspirator was attached, and 
was supplied from a tank or well, use either. 

Q. For instance, if you had neither of 
these, what would you do ? 



— 37 — 

A. Shut down the engine, close the 
damper, raise the flue caps and draw the fire, 
whichever suited the circumstances. 

Q. If your pump was turned around, could 
you feed the boiler ? A. No. 

Q. What would be the consequence ? 

A. If the packing in the pump held out, the 
plunger would exclude the air and collapse the 
discharge pipe. 

Q. Would it not have a tendency to drain 
the water out of the boiler ? 

A. No, the check valve near the boiler 
would keep it back. 

Q. If you had no check valve, what would 
it do ? 

A. The water would run out, that is, pro 
viding the pump was turned around. 

Q. If the pump plunger is one-half the 
stroke of the engine, what should the diameter 
of the plunger be ? 

A. One-third the diameter of engine cyl- 
inder. 

Q. How high should a valve lift to clear 
itself ? 



— 38 — 

A. About one-fourth of its diametor or one- 
third of its area. 

Q. What proportions should the valves be 
to any sized pump ? 

A. They should be one-fourth the area of 
the pump. 

Q. Suppose in the evening when you shut 
down, that the pump was in good working 
order, and when you started up the next morn- 
ing and opened the pump pet cock a strong 
stream of water came out both strokes: where 
would you locate the trouble ? 

A. The trouble would be at both the check 
and discharge valves being caught up. 

Q. Suppose you started the pump and it 
was in good order, and no water oame; where 
would you locate the trouble ? 

A. The suction pipe is leaking, or it is out 
of water, or there is no water. 

Q. State the usual area proportion of the cyl- 
inders of a steam pump ? 

A. The steam cylinder averages four times the 
area of the water cylinder 



THE ENGINE. 

Q. What is a steam engine ? 

A. A steam engine is a machine by which 
power is obtained from steam. 

Q. What is steam ? 

A. Steam is a gaseous vapor from water, 
generated by heat, composed of hydrogen and 
oxygen. 

Q. How do you know water is composed of 
hydrogen and oxygen ? 

A. Science shows that 1 pound of hydrogen 
with 8 pounds of oxygen is equal to 9 pounds 
of water. 

Q. What is an engine composed of ? 

A. A bed plate, cylinder, connecting rod, 
crank, crank-shaft, main pillow block, out pil- 
low block, cross-head, wrist-pin in cross-head, 
crank-pin, two cylinder heads, piston-rod, 
piston-head, follower head, bull-ring, packing- 
rings, follower plate and bolts, connecting rod 
and brasses, pillow-block brasses, a valve, and 

— 39 — 



— 40 — 

guides where the cross-head slides in, so the 
piston is kept central with the cylinder. The 
main pillow-block brasses are generally made 
into four pieces, called top, bottom and two 
quarter brasses four sides of shaft; they are 
made into four parts, so as to take up lost 
motion. 

Q. What keeps the rod from running off 
the crank pin ? 

A. The shoulder on the crank-pin. 

Q. Why are the stub ends of straps made 
heavier where the gib and key pass through? 

A. To make up for the amount of iron 
taken out for the gib and key- way. 

Q. If water should accumulate in the cyl- 
inder, what would be the consequence ? 

A. It is liable to crack the cylinder and dis- 
able the engine. 

Q. If you had charge of an engine in the 
country, and the cylinder head shonld happen 
to crack, how would you remedy it ? 

A. If not broken too bad, try to patch it 
with pieces of iron or boards, and brace it from 
the wall with a piece of heavy scantling, then 



— 41 — 

try and run the engine until a new cylinder head 
could be made. 

Q. What size should a steam pipe and an 
exhaust pipe be to any size cylinder ? 

A. The steam pipe should be one-fourth 
and the exhaust pipe one-third the diameter of 
the engine cylinder itself. 

Q. If your crank pin or other journals be- 
came hot, what would you do ? 

A. Try, while running, to get water on 
them, then oil them; if that wonld not do, stop 
and slack up the key a little, then start up 
again. All engine cylinders should be well 
drained and heated before starting, then the 
engine should be started slowly, as the water 
that accumulates in the cylinder may injure the 
piston, cylinder, or cylinder heads. Always 
leave the cylinder cocks open when not run- 
ning, and they should remain so until the cyl- 
inder is heated by the steam, — after the engine 
has been running at full speed two or three 
minutes at least. 

Q. If the cylinder had shoulders inside, and 
was out of a true circle, what would you do to 



— 42 — 

remedy it ? A. Bore it, or have it bored out. 

Q. In case^the throttle valve should become 
loose from the stem and prevent the steam 
from entering the valve chest, what would you 
do to repair it ? 

A. Close the valve next to the boiler, if 
there was one; if not, let the boiler cool down, 
then take the valve out and repair it. 

Q. If your side-valve was not steam-tight, 
what would you do ? 

A. Have the valve planed, then chip, file 
and scrape the seat to a full bearing. 

Q. If the crank and wrist-pins are worn oul 
of true, what would you do ? 

A. Caliper and file them until they were 
round and true. 

Q. What causes the wrist-pin in the cross- 
head and crank-pin to wear the way they do ? 

A. It is simply the motion they have; the 
crank goes all the way round, forming a circle, 
and the wrist only vibrates. 

Q. If the cross-head or crank-pin brasses 
were brass-bound, what should be done ? 

A. They should be chipped and filed. 



— 43 — 

Q. How do you know when you have taken 
enough off ? 

A. By outside and inside calipers. 

Q. How does steam enter the cylinder? 

A. In common slide-valve engines it enters 
through one of the end ports and exhausts back 
through the same port, when the cavity of the 
valve has covered it and the exhaust port at 
the same time. What is a cushion ? 

A. Cushion is the resistance on the oppo- 
site side of the piston-head, formed by the 
steam being shut up in the cylinder, as the pis- 
ton is nearing either dead center. 

Q. What is meant by clearance? 

A. Clearance is the space between the pis- 
ton head, cylinder head and valve face at each 
end of the stroke. 

Q. How would you know the amount of 
clearance there was in that space? 

A. By finding the number of cubic inches 
in a bucket of water, then fill up the space level 
with the steam port, and see how much water 
is left in the bucket; the difference is the con- 
tents in cubic inches. 



— 44 — 

Q. Why are gibs, keys and set screws used 
on both ends of the connecting rod? 

A. They are there to take up lost motion. 

Q. How would you do that? 

A. By loosening up the set screw, and 
driving down the key; then tighten the set 
screw to keep the key from raising. 

Q. Are there more square inches in one end 
of the cylinder than in the other? 

A. In one sense of the word there are, and 
in the other there are not, as the piston rod 
takes up some of the space in one end of the 
cylinder, therefore there is not the same area ir> 
one end as in the other. 

Q. What is a governor on an engine for? 

A. It is to regulate the steam that passes 
from the boiler to the steam chest, when the 
throttle is wide open. 

Q, How does it work? 

A. It is regulated to allow the engine to run 
at a certain speed. The governor has a belt from 
the main shaft to a pulley on the governor. 
After the engine is running up to the speed it 
is intended to, it allows only enough steam to 



— 45 — 

enter through the governor valve to keep the 
same speed; if the engine needs more power it 
begins to slack up, the governor balls drop, 
the valve opens and allows more steam to enter; 
consequently the engine must retain its speed; 
and if the load is taken off it will start to run 
away, the governor balls will rise, force the 
valve shut, and cut off the steam; consequently, 
the engine must come back to its regular speed. 

Q. How does a governor valve look? 

A. It is a round valve with grooves; there 
are different kinds, some have three or four 
openings, and some only two; the more open- 
ings the more sensitive the governor. 

Q. Are there other makes of governors? 

A. Yes, The Automatic governor on high 
speed engines, such as are used for running elec- 
tric light dynamos, they are around the shaft, 
they work direct on the valve itself. 

Q. What is a lubricator? 

A. A lubricator is an appliance for holding 
oil, to be distributed into the valve chest and 
cylinder, to prevent cutting. 

Q. How is it operated? 



— 46 — 

A. It is operated by steam forcing the oil 
out of the lubricator into the steam pipe. 

Q. Where is the lubricator generally at- 
tached. 

A. In the steam pipe immediately over the 
throttle or globe valve, used to start and stop 
the engine. 

Q. State the principal upon which a jet of steam 
taken from the boiler at boiler pressure can 
force a stream of water back into the boiler 
through the injector? 

A. It acts upon the principal of a light body 
moving at a high velocity giving a slower motion 
to a heavier body effecting an entrance by means 
of the momentum thus given to it. For ins- 
tance, steam at the pressure of 80 lbs. to the 
square inch will escape into the air with a velo- 
city of 1,821 feet per second or 1,241 miles per 
hour. This rapidly moving jet of steam causes, 
at first a vacuum in the casing of the injector, 
which fills with water. The steam then mingles 
with the water, condenses and imparts its velocity 
to it. The stream of water is then forced along 
the pipe and strikes the check valve with a force 
sufficient to open it and then enters the boiler. 

Q. Will the injector work if the water that is 
supplied is to hot to condense the steam. See p. 95. 



LINING AN ENGINE. 

Q. How would you line up an engine? 

A. By stripping the engine, take off both 
cylinder heads, if convenient,; then take out the 
follower-head, piston-rings, bull-ring; discon- 
nect the piston from cross-head: also disconnect 
the connecting-rod from the cross-head and the 
crank-pin; then take a slotted stick and place 
it on one of the studs on the end of cylinder 
furthest from the crank; then draw a fine sea- 
grass line oyer the point of stick and through 
the center of cylinder, and attach it to a stick 
at the other end of the bed-plate, nailed to the 
floor or clamped to the bed-plate; then take a 
thin stick, the length of it being a half inch 
less than half the diameter of cylinder, and 
stick a pin in each end of the stick, so they can 
be forced in or drawn out to suit the adjust- 
ment; then center the line at each end of the 
cylinder at the counter-bore from four sides. 

— 47 — 



— 48 — 

Never center the line in the stuffing box where 
the piston passes through, but use the inside 
counter-bore under all circumstances, whether 
you can remove the back cylinder head or not. 
Some engine cylinder heads and fram^ are 
one; consequently, the head cannot an J must 
not be moved. 

Q. If one counter-bore would be out, or 
larger than the other, what would you do ? 
Would it not throw the bore of the cylinder or 
the line out? 

A. No; center it accordingly; it would not 
make any difference, only two centering sticks 
with pins are needed to bring the line central 
with the bore. 

Q. Why do you use the counter-bore? 

A. Because the counter-bore is the only true 
bore the cylinder has that is not worn; conse- 
quently, all engineers and machinists must be 
governed by it. Q. What is a counter-bore? 

A. A counter-bore is each end of the cylin- 
der bored from y 1 ^ to \ of an inch larger, from 
1 to 4 inches long, according to the size and 
length of the cylinder. 



— 49 — 

Q. What is a counter-bore for? 

A. To keep the piston from wearing a 
shoulder in the cylinder at each end. 

Q. Why is it that the piston does not wear 
a shoulder in the cylinder? 

A. Because the piston rings just pass over 
the edge of the regular bore, and by so doing 
no shoulder can be formed in the cylinder. 

Q. How are cylinders bored? 

A. They are generally bored on a regular 
cylinder boring lathe, which has a table that 
can be raised or lowered to suit. The regular 
bore is first bored, then the counter-bore, then 
the two faces for the heads. 

Q. How do you square a shaft when you 
have got the line centrally through the cylin- 
der? 

A. Move the crank-pin down to the line 
and see where the line touches the crank- 
pin between the two shoulders, then move 
the pin over to the other dead center, and see 
how itcomes; if equal, the shaft is square. 

Q. If you found it out of square % inch, 
what would you do? 



— 50 — 

A. Move the out end pillow-block. 

Q. Why not move the head-block. 

A. Because it would alter the length of the 
connecting-rod, and be liable to knock out a 
cylinder-head. 

Q. How would you level a shaft? 

A. A shaft is leveled by a spirit level, or a 
plumb-line dropped past close to the line that 
comes through the cylinder directly in front of 
the center of shaft; let it drop in a bucket of 
water to keep the plumb-bob from swaying 
around; then try the crank pin at both half- 
strokes (the same principle as in squaring), top 
and bottom, and see how the crank-pin feels the 
line; if equal, the shaft is level. 

Q. Is there no other way to level a shaft? 

A. Yes, by the pulley wheel. 

Q. How is it done? 

A. Drop a plumb-line down from the ceil- 
ing, past the rim's edge of the wheel, directly 
over the center of the shaft; let the space be- 
tween the plumb line and rim be one inch; 
mark the wheel with chalk for a starting and 
stopping point, and caliper the distance with 



— 51 — 

inside calipers; then turn the wheel and shaft 
around, and continue calipering until the wheel 
has made a full revolution; if it calipers the 
same all the way around, the shaft is level. 
This principle answers for trueing a wheel as 
well as leveling a shaft. The former way, by 
dropping a p]umb-line in front of the crank face 
and feeling the line with the crank-pin at both 
half strokes, is the proper way to level a shaft. 

Q. If you found the shaft out of level, 
what would you do? 

A. I would have to thin or thicken the 
brasses, or babbitt the main pillow and out 
block bearings, whichever the case may be. 

Q. How would you know if the center of 
the shaft is in line with the line through the 
cylinder or not? 

A. It can be found out by placing a two- 
foot steel square against the crank face, under 
the line through the cylinder, so that the heel 
of the square is at the center of the shaft, and 
see how the square touches the line ; if it 
touches exactly, the shaft is in line; if too hard, 
the shaft is high; if not at all, the shaft is low. 



— 52 - 

Q. How would you raise your shaft? 

A. There are various ways ; by liners, bab- 
bitt, heavier or lighter brasses. 

Q. If your crank face was oval, and you put 
a square against it, would that be right ? 

A. A spirit level could be placed on a square 
and bring it level, or drop a plumb-line, and 
put the end of the square against the crank- 
shaft center, and let it come against the plumb- 
line. This is a very true way. 

Q. Now, after your shaft is in line, square 
and level, and you still find it out over line J 
inch, what would you do? 

A. I would take it off the crank-pin brasses 
and fill in the other side with a brass ring, or 
babbitt the side edge of brasses; in some cases 
the side of the connecting rod has to be chipped 
to allow it to pass free of the crank-face. 

Q. Why would you not take it off the wrist- 
pin brasses in the cross-head? 

A. Because the rod would then be out of 
the center of cross-head, and have a tendency to 
bind the piston iu the cylinder and the cross- 
head in the guides, consequently cutting both. 



— 53 — 

Q. Woulci it not make a difference at the 
other end of the rod? 

A. No, the closer the crank-face the better 
it would be. 

Q. Now what would you do? 

A. Level and line the guides by putting 
them in their place, and line them with a pair 
of calipers, by calipering them at both ends to 
get them in line with the line through the cyl- 
inder, after having found the distance between 
the side of the cross-head and the center of the 
cross-head where the piston enters the cross- 
head. Level by spirit level, first taking spirit 
level and trying it in the cylinder, if a new one, 
or on top of the cylinder where it has been 
planed off when first bored, for they are the 
only things to go by. 

Q. Would you use the valve seat to level 
by? 

A. No, but alongside of it, where the steam 
chest rests on. 

Q. If you had no spirit level, how would 
you do it? 

A. With a plumb-line, by placing a square 



— 54 — 

lengthwise on the guides, and try them by- 
bringing the square against the line. 

Q. If you had no two-foot square, and could 
not get any, how would you lay one off ? 

A. Take a pair of dividers, draw a circle, 
then find four points on the circle, scribe lines 
from point to point, which gives a square. This 
should be done very accurately, or 6, — 8 and 10. 

Q. Can a plumb-line hang out of true? 

A. It can not, provided it hangs clear of 
everything. If none of these were handy, a 
straight edge must be placed across the guides 
at one end, and see if the guides touch the 
straight edge equally at both edges, then cali- 
per the distance between the line and the straight 
edge, also at the other end of the guides; if the 
same, the guides are level lengthwise with the 
cylinder and line; then level the guides cross- 
wise with a plumb-line and square. 

Q. How would you measure the connect- 
ing rod of an engine? 

A. By finding the striking points. 

Q. How wodd you do that? 

A. By shoving the piston and cross-head up 



— 55 — 

against the cylinder-head, and making a mark 
on the guides at one end of the cross-head with 
a scriber and center-punch; then move the pis- 
ton and cross-head back to the other cylinder- 
head and make another mark on the guide at 
the same end of the cross-head; then measure 
from the center of crank-pin to center of shaft; 
that gives the half -stroke; double this, gives full 
stroke. If half-stroke is 12 inches, the full 
stroke is 24 inches; then if the distance between 
the two striking points is 25 inches, aad the 
stroke 24 inches, the clearance between the cyl- 
inder-head and piston-head will be -| inch when 
the piston is at either end of the cylinder. 
Then move the cross-head ^ inch back from the 
striking point, and bring the crank-pin toward 
the same dead center; then take a tram and 
measure from the outside center o£, crank-pin 
to the outside center of wrist pin in cross-head, 
which will give proper length of connecting- 
rod, albO the right division of clearance. 

Q. What is meant by clearance in the cyl- 
inder? 

A. It is the unoccupied space between the 



— 56 — 

piston-head, cylinder-head and valve-face, when 
the crank-pin is at either dead center. 

Q. Does the amount of clearance affect the 
engine's economy? A. Yes, it does. 

Q. How much clearance should there be be- 
tween the piston and cylinder-head? 

A. It depends upon the size; some have from 
'£ to $■ of an inch. 

Q. What is formed in that space or clearance 
when running? A. A cushion. 

Q. What is a cushion ? 

A. A cushion means the steam that enters 
the cylinder through the lead the valve has, and 
the resistance it makes on the piston- head, cyl- 
inder-head and valve-face, as the engine is 
reaching the dead-center. 

Q. What is a cushion for? 

A. It is to catch the piston and weight of 
the machinery as it reaches the dead-center, and 
the lead is to give the engine power at the be- 
ginning of the stroke. 

Q. How does it act? 

A. The same as a spring on the end of a 
hammer. 



— 57 — 

Q. If you wished to shorten or lengthen the 
connecting-rod, how could it be done? 

A. By placing tin or sheet iron liners be- 
tween the brasses and stub-ends of the connect- 
ing-rod. 

Q. Now, if the key had to be raised, how 
could this be done? 

A. By putting liners between the straps and 
brasses. 

Q. Would that not alter the length of the 
rod? A. No. 

Q. With what instrument would you meas- 
ure a connecting-rod ? 

A. It is called a "tram." 

Q. With what is an engine packed in the 
stuffing-box? 

A. Some engineers use hemp, others use 
black lead packing, and others use lead rings or 
metalic packing; there are several kinds. Every 
engineer to his own taste. 



VALVE MOTION. 

Q. What is an eccentric? 

A. An eccentric is a subterfuge for a crank; 
it is anything out of center. 

Q. How would you find the throw or stroke 
of an eccentric? 

A. By measuring the heavy and the light 
side; the difference between the two is the 
stroke or throw. 

Q. What throw should a common slide valve 
engine eccentric have? 

A, Generally double the width of the entry 
or steam ports. 

Q. If you changed the size of the eccentric 
would it alter the throw of the valve ? 

A. No, it would not, but if you changed the 
position of the eccentric on the shaft it would. 

Q. What is a cam? 

A. A cam has no definite meaning; it has 1 
2, 3 or 4 motions; they are used on poppet valve 

-58 — 



— 59 — 

engines, such as are in use on high pressure 
river steamboats. 

Q. How would you measure your valve and 
eccentric rods? 

A. By placing the crank-pin at its dead-cen- 
ter, the center of the eccentric straight or plumb 
above the center of the shaft, the rocker-arm 
perpendicular, and the valve covering both 
ports equally; then take a tram and measure 
from the center of the eccentric to the center of 
the pin where the eccentric rod hooks on (gen- 
erally the lower pin) for the eccentric rod, and 
from the outside center of the pin where the valve 
rod is attached to the furthermost end of the 
valve, allowing for two nuts at each end of the 
valve, called adjusting and jamb nuts. 

Q. How would you plumb an eccentric? 

A. By dropping two plumb lines, one at 
each side of the shaft, and half the space be- 
tween the two lines will be where the center of 
the eccentric should stand, with heavy side up. 

Q. What kind of a tool would you use to 
find the exact center? 

A. A pair of hermaphrodite calipers, one leg 



— 60 — 

of which has a sharp point and the other leg 
has a short foot, so as to feel the line. 

Q. What does an eccentric rod consist of ? 

A. An eccentric rod consists of a strap, 
yoke, rod and two nuts; when taking the meas- 
ure, couple the yoke and strap together, then 
put a half-inch thick piece of wood between the 
two straps and find the center of the circle from 
four sides, with a pair of hermaphrodite cali- 
pers, then put the rod in the yoke and "adjust it 
to the proper length by the two nuts; if that 
will not do, the rod must be shortened or length 
ened, by cutting out or adding a piece, which- 
ever the case may be. Then take the measure 
with a tram from the center of the straps to the 
center of the rod where the rod hooks on lower 
rocker-arrn pin. 

Q. How long is the thread on a valve-rod? 

A. Long enough to allow two nuts at each 
end of the valve, and space for adjustment. 

Q. Now, if your rocker-arm stood at a quar- 
ter, and your eccentric out of plumb, how would 
you take the measure for the rods? 

A. Simply bring them plumb and take 



— 61 — 

the measure; that is the only right way. 

Q. After you have measured the rods, 
what would you do ? 

A. They should be put on and the valve set. 

Q. What do you move or do first, to set a 
valve after connections are made? 

A. Move the eccentric in the direction the 
engine is to run, until the valve begins to take 
steam or lead, then tighten the eccentric tem- 
porarily with set screws, then move the crank- 
pin over to the other dead center, and see 
how much lead it has; if equal the valve is set. 

Q. What is meant by the lead of valve? 

A. The opening the valve has when the pis- 
ton is at the beginning of its stroke. 

Q. What lead should large engine have? 

A. About -Jg- of an inch. High speed en- 
gines must have a quick opening or good lead. 

Q. Now if you find the valve laps out § of 
an inch on one end, and the proper lead on the 
other, what would you do? 

A. Divide the difference, by moving the 
valve one-half it is out, by adjusting the valve- 
gear. Q. How much? 



— 62 — 

A. The valve has -^ of an inch lead at one 
end and laps f of an inch at the other end; the 
valve is out T \ of an inch; then the valve must 
be adjusted by the nuts one-half it is out, mak- 
ing j\ of an inch. Then throw the crank on 
the other dead center, move the eccentric 
whichever way will bring you back to y 1 ^ of 

an inch lead, then tighten temporarily with 
set screws, throw crank over on the other dead 
center, and the valve will be set. After valve 
is set, tighten the eccentric for good. 

Q. But if it is not set, what would you do? 

A. Go through the same performance until 
it is set. Some valve-rods have a yoke that slips 
over the valve, while the adjusting and jam-nuts 
are between the stuffing box and the rocker-arm 
pin. When a valve-rod has no nuts, the adjust- 
ing must he done at the eccentric rod. To 
lengthen or shorten the stroke of valve-rod, 
raise or lower the eccentric-rod pin in the slot, 
at the bottom of the rocker-arm, whichever way 
suits the circumstances. 

Q. Now, after you have set your valve, 
keyed everything up properly, and there was a 



— (53 — 
thud or dead sound in the engine or cylinder, 
what would you do, or where would you look 
for the trouble? 

A. In the exhaust being choked. The steam 
chest cover must be taken off, then uncouple 
the valve, turn the valve up sideways and move 
it until the steam edge has the proper lead with 
the steam-port, then place a square on the valve- 
seat of the cylinder, and against the valve-face, 
to see how the exhaust lead on the opposite 
steam-port corresponds; if it is choked, then 
scribe it by allowing a little over double the 
steam lead. 

.Q How is the exhaust made larger? 

A. By chipping out the exhaust cavity in 
the valve, and rubbing file over it to smooth it. 

Q. Do you think a little over double the 
steam-lead would be sufficient for the exhaust? 

A. Yes, if not, take out a little more. 

Q. Where should the exhaust be? 

A. It should be the furthest from the 
steam-port that is receiving. 

Q. What would you do in case your eccen- 
tric slipped around on the shaft? 



— 64 — 

A* Set the valve the same as before. 

Q. Is the principle of valve setting the 
same on all engines? 

A. Yes; some engines have two steam and 
two exhaust valves, but that makes no differ- 
ence, the principle is the same. (See p. 96). 

Q. How would you find the dead center of 
an engine? 

A. By placing a spirit level on the strap 
that goes around the brasses that connect the 
crank-pin to the connecting-rod, and when it is 
level the crank is at a dead center. If the 
engine is not level, then use an adjnstible level. 

Q. What other way could you find the dead 
center of an engine? 

A. By moving the engine toward the dead 
center until the cross-head stopped moving; 
then put a center punch mark in the floor, and 
one on the fly-wheel, after having marked it 
with a tram; then move the crank over the 
center until the cross-head begin to move, 
then put another mark; the middle between 
the two marks is the exact dead center; then 
bring the middle mark to the point of the 



tram; this is done with a small tram with one 
straight point and a short foot. 

Q. If the engine had to be run in the op- 
posite direction to which it had been running, 
how could it be done ? 

A. It could be done by placing the crank- 
pin on the dead center, removing the steam- 
chest cover, and turning the eccentric over on 
the shaft in the opposite direction, until the 
valve has the proper lead at the opposite port, 
then try the eDgine from dead center to dead 
center, to equalize the lead at both ends of the 
valve; then the engine will run in the opposite 
direction. 

Q. Does a crank-pin and piston travel the 
same distance? 

A. No, a crank-pin travels lyVVoV times 
further than the piston each revolution, or 
O-iVoVo times further each stroke. For exam- 
ple, take an engine with a 12-inch stroke, the 
piston travels 24 inches and the crank pin 
3 ^T 6 owo inches each revolution, or the piston 
travels 12 inches each stroke and the crank-pin 
18.8496 per single stroke of piston. To do 



— 66 — 

this, multiply the single stroke by one-half of 
3.1416, which is 1.5708, and the answer will be 
the distance the crank-pin travels further than 
the piston per single stroke. This rule 
answers for all engines. Another fact not gen- 
erally known by many men is that a crank of 
an engine, at two certain points, travels a long 
distance while the motion of the cross-head is 
hardly noticed. When the center of the crank- 
shaft and crank-pin are in a line with the 
piston-rod, no steam pressure applied to either 
side of the piston can set the engine in motion; 
this is called the dead center. 

Q. Is the piston-head in the center of the 
cylinder when the centers of the crank-pin and 
crank-shaft are plumb, or in right angles with 
the cylinder? 

A. No, under no circumstances. 

Q. What is a revolution? 

A. It means the crank has turned once 
around, or made a circle. 

Q. How many strokes has a revolution ? 

A. Two to each revolution. 

Q. If an engine has 24 inches stroke, and 



makes 65 revolutions per minute, how many 
feet does it travel in a minute? 

A. Twenty-four inches multiplied by 2 
equals 48 inches, this multiplied by 65 revo- 
lutions equals 3120 inches, which divided by 
12 equals 260 feet per minute, 

Q. If you were asked the horse power of 
any sized engine, could you tell it? A. Yes. 

Q. Well, how would you go about it, and 
what is a horse power? 

A. A horse power is 33,000 pounds raised 
I foot high in 1 minute, or 150 pounds raised 
220 feet high in 1 minute. To find the horse 
power of any engine, first find the area of the 
piston-head face, then multiply the answer by 
the average pounds pressure per square inch in 
cylinder, then multiply by the number of feet 
traveled in 1 minute, and divide by 33,000. 

EXAMPLE: 
Cylinder 12 x 24 in. 12 diam. of cylinder. 

65 revolutions, 12 

Average pressure 40 ft>s. 144 sq. of diameter. 

.7854 
Generally allow 

pre 8 U sU i^flgurllfg 113 - 09 ^ area of p. h. face. 

H. p. 40 average pressure in 

the cylinder. 

4523.9040 

260 No. ft. trav. by p. 



33000)1176215.0400(35.6428 I. H. P. 



THE INDICATOR. 

The steam engine indicator is an instrument 
for showing the pressure of steam in the cylin- 
der at all points of the stroke, or for producing 
actual diagrams. The indicator consists of a 
small cylinder accurately bored out, and fitted 
with a piston, capable of working in the (indi- 
cator) cylinder with little or no friction, and 
yet be practically steam-tight. The piston has 
an area of just -J of a square inch, and its mo- 
tion in the cylinder is |f of an inch. 

The piston-rod is connected to a pair of light 
levers, so linked together that a pencil carried 
at the center of the link moves in nearly a 
straight line through a maximum distance of 
3^ inches. A spiral spring placed in the cylin- 
der above the piston, and of a strength propor- 
tioned to the steam pressure, resists the motion 
of the piston; &nd the elasticity of this spring 
is such that each pound of pressure on the pis- 
ton causes the pencil to move a certain fraction- 

— 68 — 



— 69 — 

(al part of an inch. The pencil in this case is 
made of a piece of pointed brass wire, which 
retains its sharpness for a considerable time, 
and yet makes a well-defined line upon the pre- 
pared paper generally used with the indicator. 

The paper is wound around the drum, which 
has a diameter of 2 inches, and is capable of a 
semi rotary motion upon its axis to such an 
extent that the extreme length of diagram may 
be 5^ inches. Motion is given to the drum in 
one direction, during the forward stroke of the 
lengine, by means of a cord connected indirectly 
to the cross-head of the engine, and the drum 
is brought back again during the return stroke 
of the engine by the action of a coiled spring at 
its base. 

The conical stem of the instrument permits 
it to be turned around and fixed in any desired 
position, and the guide-pulleys attached to the 
instrument under the paper drum may also be 
moved around so as to bring the cord upon the 
drum-pulley from any convenient direction. 

The upper side of the piston is open to the 
atmosphere; the lower side may, by means of a 



— 70 — 

stop-cock, be put into communication either 
with the atmosphere or with the engine cylin- 
der. 

When both sides of the piston are pressed 
upon by the atmosphere, the pencil, on being 
brought into contact with the moving paper, 
describes the atmospheric line. When the lower 
side of the piston is in communication with the 
engine cylinder, the position of the pencil is 
determined by the pressure of the steam exist- 
ing in the cylinder; -and on the pencil being 
pressed against the paper during a complete 
double stroke of the engine, the entire indicator 
diagram is described. 

In order that the diagram shall be correct, 
the motion of the drum and paper shall coincide 
exactly with that of the engine piston; second, 
that the position of the pencil shall precisely 
indicate the pressure of steam in the cylinder; 
third, that the pendulum must be from 1|- to 3 
times as long as the stroke of the engine piston; 
fourth, that the pendulum must be plumb when 
the piston is at half-stroke; fifth, that the cord 
around the drum must be attached to the pen- 



— 71 — 

dulum at right angles, or square with the indi- 
cator; sixth, the pendulum must be attached 
with an inch wooden pin to the ceiling or floor 
at one end, the other end to the cross-head by 
means of a screw bolt in the wrist-pin and a 
slot in the pendulum; seventh, that the two holes 
tapped in the cylinder are directly opposite the 
steam ports, and centrally between the piston- 
head and cylinder head, when the engine is at 
the dead center, or, in other words, in the cen- 
ter of clearance; eighth, that the piping should 
be as short as possible, and -J- inch pipe if not 
over 1 foot long. If longer the pipe should be 
larger close to the cylinder, and covered so as 
not to allow too much condensation, as it affects 
the diagram. The best way to take a diagram 
is to tap a hole in each cylinder-head and take 
each end separately. The cord must be attached 
to the pendulum, so the paper drum will move 
in proportion to the piston. 

An indicator shows the highest and the low- 
est pressure reached, also the cut-off and lead. 
If there is a great difference, say more than 5 
pounds, between the boiler pressure and the 



— 72 — 

initial pressure upon the piston 4 the connecting 
pipes may be taken as being too small, too 
abrupt, or the steam ports too contracted. The 
full pressure of steam should come upon the 
piston at the very beginning of its stroke. 
Should the admission corner be rounded, the 
valve is wanting in "lead," or, in other words, 
the port for the admission of steam is uncovered 
too late in the stroke. 

The steam line should be parallel or straight 
with the atmospheric line up to the point of 
cut-off, or nearly so. Should it (the steam line) 
fall as the piston advances, the opening for the 
admission of steam is insufficient, and the steam 
is "wire-drawn." 

The point of cut-off should be sharp and well 
defined; should it be otherwise, the valve does 
not close quick enough. The bevel line leading 
from the cut-off line to the end of the stroke is 
called the expansion line. 

Q. Which is the standard indicator? 

A. The Tabor's improved. 

Q. Are there any other makes? A. Yes; 
Richard's, McNought's, Thompson's and others. 



RULES. 

Rule for telling the power of a diagram: 
Set down the length of the spaces formed by 
the vertical lines from the base in measure- 
ments of a scale accompanying the indicator, 
and on which a tenth of an inch usually rep- 
resents a pound of pressure ; add up the total 
length of all the spaces, which will give the 
main length, or the main pressure upon the 
piston in pounds per square inch ; to do this, 
lay a card taken by the indicator off in ten 
parts, by drawing lines from top to bottom. 
Find out what the scale is; suppose it is 60, the 
number of ordinates 10, and that the sum of 
their length is 6 inches; so 6 and 10 ordinates 
= y 6 ^ or 6 x 60 = 36.0. Answer, 36 pounds 
pressure upon the piston. 

Rule for finding and deducting friction : 
Multiply N. H. P. by. 13 and subtract the answer 
from N. H. P., which gives I. H. P. 

-73- 



— 74 — 

Q. What is N. H. P.? 

A. It is nominal horse power. 

Q. What is I. H. P.? 

A. It is indicated horse power. 

Q. What is meant by cutting off steam at 6 
inches? 

A. It means that the valve closes and cuts 
off the live steam from the boiler at 6 inches of 
the piston's travel; then the engine gets its' 
power, from the time the valve closes or cuts 
off until the exhaust opens, by the expansion of 
the steam closed up in the cylinder. 

Standard multiplers, with examples : 

1. For the Area of a Circle. Multiply sq.. of diam, by .7854 

2 For Circumference of a Circle, Multiply diameter by 8.1416 

3. For Diameter of a Circle, Multiply the circum. by .31831 

4. For the Surface of a Ball, Multiply sq of diam. by 3.1416 
6. For the Cubic Inches in a Ball, Multiply Cube of dia. by .6236 

1. Rule for finding the area of any circle. 
Always multiply the diameter by itself, then by 
.7854, then cut off 4 decimals to the right. 

2. Rule for finding the circumference of 
anything round. Multiply the diameter by 
3.1416, and cutoff 4 decimals. 

3. Rule to find diameter of circle. Multi- 
ply circumference by .31831. 

Example: The circumference 9.4248 x .31831 => 
3.000008088 = 3 inches diameter. 



— 15 — 

4. Rule to find the surface of a sphere, 
globe or ball. 

Example: 9 inches diameter x 9= 81 X3.1416 = 
2,54.4696. 

5. Rule to find the cubic inches in a ball. 
Multiply cube of the diameter by .5236; the 
answer equals its solid contents. 

Example : Ball 3 inches in diameter; 3x3 = 9 
9x3 = 27 x .5236 = 14 T VVo 2 o solid contents. 

Rule to find pressure on the crown sheet of 
a hanging fire-dox boiler. Multiply the width 
by the length in inches, then multiply by steam 
gauge pressure and devide by 2. 

EXAMPLE: 

Crown sheet 46 x 33 in. 46 

Pressure 85 lb. 33 

Iron i in. 1518 

85 



If iron is i in. div. by 4. 2)129030 

If iron is f in. div. by 2.66 2000)64515 lbs. press'e. 

32.s_6Jtons " 
Rule to find how much water a boiler will 
contain. For 2-flue boiler, § full of water, find 
| of the area of the boiler in inches inside; mul- 



— 76 — 

tiply by length in inches; then find area of flues, 
thickness of iron added; then multiply by 2, if 
two flues; multiply by length in inches, subtract 
area of flues from § contents, and divide by 231 
(number of cubic inches in a standard gallon); 
the answer will be the number of U. S. gallons. 





EXAMPLE : 


Boiler 48 inches. 
Two flues, 16 in. 


48 
each. 48 


Length 20 feet. 


2304 


16 


.7854 


16 


3)1809.5616 area of Boiler. 


256 

.7854 


603.1872 One-third of area. 

2 


•201.0624 

2 


1206.3744 Two-thirds of area 
240 Length in inches. 


402.1248 


289529.8560 


240 


96509.9520 Sub. Area of Flues, 


96509.9520 


231)193019.9040 



835.5940 No. of Gallons. 

Rule to find the amount of water required, 
when the average pounds of coal used per hour 
is known. Divide the coal by 7.5; the answer 
will be cubic feet; then multiply by 7.5, and 
that gives the number of TJ. S. standard gallons. 



— 77 — 

EXAMPLE : 

117 lbs. of coal used per hour, 7.5]117.0 



15-6 
7.5 



117-0=117 gals. 

Q. How many cubic feet in 1 lb. of air? 

A. 13 T 8 oyo* cubic feet. 

Q. How much air does it take to consume 1 
pound of coal? 

A. It takes 18 pounds, or 248 T y ) - D 6 s - cubic feet. 

Q. How would you tell the amount of water 
any tank contained? 

A. If the tank was large at the bottom and 
narrow at the top, lay the tank off in 10 parts 
from top to bottom, then take the diameter •£$ 
from the large end of the tank, square it, then 
multiply by .7854; that gives the area; then 
multiply quotient by full depth of tank and 
divide by 1728, which gives the number of 
cubic feet; multiply answer by 7.5, and the 
number of U. S. gallons will be given. The 
example must be done in inches; 1728 is the 
number of inches in a cubic foot, and 7.5 is the 
number of gallons in a cubic foot. 



— 78 — 

EXAMPLE: 

Tank 2 feet diam. 24 inches diameter. 
Tank 3 feet deep, 24 " " 

576 

.7854 



452.3904 area in inches. 
36 inches deep. 



1728)16286.0544 



9.4218 cubic feet. 

7.5 jSIo. gals, in a cub. ft. 



70.86000 U. S. gals, in tank. 

Rule how to mark engineer's tools. Warm 
the tool and allow a thin coat of beeswax to 
cover the place to be marked; after the bees- 
wax is cold, take a dull scriber and do the 
marking; then apply some nitric acid, after a 
few moments wash off the acid with water, 
then heat the tool to melt the beeswax, and 
you will find well defined marks. 

Rule for chimneys. Chimneys should be 
round inside, instead of square, to insure a 
good draft. The opening should be one-fifth 
larger than the area of the flues or tubes com- 
bined; if less, the draft will not be free. The 
opening from the bottom shoulcj increase ii} 



size to the top, and be smooth inside. 

Rule for making good babbitt metal, fof 
high and low speed, in parts. 



HIGH SPEED. 


COMMON. 


MEDIUM. 


Martin's Nickel. 


10 

16 

4 

70 


Copper 


12 

4 
84 


Copper 

Antimony 

Tin * 


60 


Copper 

Antimony 

Tin 


Antimony 

Tin 


25 
15 












100 




100 




100 



Rule for babbitting a box. Nearly every 
engineer has his own way; but the best and 
quickest way is to chip out all the old babbitt 
in the cap and box, then put the journal or 
shaft that is to run in the box in its place; put 
enough liners in between the shaft or journal 
and edge of box until level, square and in line; 
put thick putty around the shaft and against 
the box, so the babbitt can not run out; then 
heat the babbitt until it runs free, and pour 
accordingly; the cap is then bolted in its place 
upon Jg- inch thick liner, and putty placed as 
before; then pour metal through the oil 
holes, which will have to be drilled out after- 
wards. 



— 80 — 

Rule to determine the capacity of any size 
pump, single or double action. Multiply the 
area of the water piston-head face or plunger 
in inches, by its stroke in inches, which gives 
the number of cubic inches per single stroke; 
the answer divided by 231 (the cubic inches in 
a gallon) will give the .number of standard gal- 
lons per single stroke. But remember, all" 
pumps throw less water than their capacity, 
which depends upon the condition and quality 
of the pump. This loss arises from the rise 
and fall of the valves; from a bad fit or leak- 
age, and in some cases from there being too 
much space between the valves, piston or plun- 
ger. The higher the valves have to rise to 
give the proper opening, the less work the 
pump will perform. 

Q. Will a boiler 60 inches in diameter, 
§ inch iron, stand as much pressure as a boiler 
48 iuch diameter, £ inch iron? A. No. 

Q. Why? 

A. Because the pressure in the large boiler 
has more surface, and will not allow it. It is 
the same as a long bar and a short bar of the 



— 81 — 
same thickness; it takes less strain to break 
the long one than the short one. 

Rule for finding safe working pressure of 
steam boilers. Always use .56 for single riv- 
eted and .70 for double riveted side seams. A 
radius means \ the diameter and \ of ten- 
sile strength is safe load. XL S. standard is \. 

Multiply the thickness of iron by single or 
double rivets, then multiply by the safe load, 
divide by internal radius, and the answer will 
be the safe working pressure. 
EXAMPLE: 
Diam. 42 in. .1875 thickness of iron. 

Iron T 3 ^ in. .70 double riveted. 

Double riveted .131250 

50,000 lbs. tensile str'th. 10000 2)42 

20.8125)13125000.00 21 J2g** e 
Safe working pressure, 63.06 .1875 

5 20.8125 £**• 

Bursting pressure, 315.30 

Rule to find aggregate strain caused by the 

pressure of steam on the shells of boilers. 

Multiply the circumference in inches by the 

length in inches; multiply this answer by the 



— 82 — 

pressure in pounds. The result will be the 

pressure on the shell of boiler, and divide by 

2000, which gives the tons. 

EXAMPLE; 
Diam. of boiler 48 inches, circumference 150.7968, 
length 20 feet, or 240 inches, pressure of steam 120 
lbs. 150.7968 x 240 x 120 = 4342947.8400 lbs., divided 
by 2000 = 2171* tons strain. 

Rule to find the number of feet of 1 inch 
pipe required to heat any size room with steam. 
For direct radiation 1 lineal foot (straight foot) 
to 25 cubic feet of space. For indirect radia- 
tion, 1 lineal foot to 15 cubic feet of space. 
Note, all pipe is measured inside for size. 
EXAMPLE: 

Room 18x18x18 to be heated with 1 inch 

pipe. Direct radiation. All calculating must 

be done in inches, and divided by 1728 to find 

the cubic feet. 

216 
216 



46656 
216 



1728)10077696 cubic inches. 

25)5832 cubic feet. 
Lineal 233^- feet of 1 inch pipe. 



— 83 — 

One cubic foot of boiler is required for every 
1500 cubic feet of space to be warmed. One 
horse power of boiler is enough for 40,000 
cubic feet of space. 

Rule to find the horse power of a boiler. 
Always find the number of square inches and 
divide by 144, which gives the square feet of 
heating surface, and divide by 15 square feet, 
whcih is an average allowance for one horse 
power of a boiler; divide the H. P. by 2, you 
will have the proper grate surface, and allow 
£ square inch of safety valve to each square 
foot of grate surface. Generally, from £ to f 
of a square foot of grate surface is allowed to 
each horse power of a boiler. 

Q. How do you find the horse power of a 

boiler? 

A. Find the number of square feet of heat- 
ing surface and divide by 15; 15 square feet of 
heating surface is the general allowance for a 
E, P. of a boiler, (See following example.) 



— 84 — 

EXAMPLE: 

Boiler 48 in. x 25 ft. First find circnm. of boiler. 
Two 16 in. flues. 16 in. diam. of 1 flue. 

48 diam. of shell. 3.1416 

3.1416 50.2656 circ. of 1 flue. 



3 )150.7968 300 length of flue. 

50.2656 one-third eircum. 15079.6800 in inches. 
2 2 

100.5312 two-thirds u 30159.3600 heat. sur. 2 fl. 
300 length or boiler in inches . 



30159.3600 No. sq. in. heat. surf. 16 in diam. of 1 flue, 
in the shell. _16 

48 • 256 

48 .7854 



2304 201.0624 area 1 flue. 

JT854 2 



3)1809.5616 area of 1 head. 402.1248 area 2 flues, 

603.1872 one-third area of 1 hd. 2 



804.2496 both ends. 



1206.3744 two-thirds area of 1 hd. 
2 



2412.7488 two- thirds area of both heads. 
No. sq. in. heat. surf, in shell, 30159.3600 
" " flues, 30159.3600 

Two-thirds area both heads, 2412.7488 

Total, 62731.4688 

Subtract area of flues, 804.2496 

This boiler is 28 h. p. An 144)61927.2192 
engine uses about i of boil- 15( 430. sq. ft. h. s. 
er's h. p., making this boil- 2( 28. h. p. 
er sufficiently large enough 2( 14. grate surf, 
to supply engine of 66 h. p. 7. area s'fty v. 



— 85 — 



Number sq. feet of heating surface allowed for 
tubXr boilers are 12 sq. feet. Flue boilers 15 sq. 
feet. Cylinder boilers 7 sq. feet. 

Rule to find the horse power generated in 
any kind of boiler when running. First, notice 
how long it will take to evaporate 1 inch of 
water in the glass gauge, divide this into 60, 
which gives the number of inches evaporated 
in one hour; second, multiply the average di- 
ameter where evaporation took place by the 
length of the boiler in inches; this multiplied 
by the number of inches evaporated, and the 
answer divided by 1728 gives the cubic feet of 
water evaporated in one hour. 

As a rule, 1 cubic foot of water evaporated is 
generally allowed for 1 horse power; also the 
capacity of a pump or injector for any boiler 
should deliver 1 cubic foot of water each horse 
power per hour, and an engine uses one-third 
of a cubic foot of water per horse power. 
EXAMPLE: 

Length of boiler 216 inches. 216 

Average diarn. 40 inches. _JW 

One inch evaporated in 15(60 8640 

l^mimitfiS. 4 4 



15 minutes. 



1728)34560(20 h. p. 



— 86 — 

Weight of Square Superficial Foot of 
Boiler Plate when Thickness is Known. 



Thickness. 


Weight. 


Thickness. 


Weight. 


Inches. Dec. 


lbs. 
1.25 


Inches. Dec. 


lbs. 


£g ■= .03125 


T V = .3125 


12.58 


T V = .0625 


2.519 


| = .375 


15.10 


^_. — .0937 


3.788 


T \ = .4375 


17.65 


i = - 125 


5.054 


* =.5 ' 


20.20 


A = .1562 


6.305 


T \ = .5625 
1 = .625 


22.76 


T \ = .1875 


7.578 


25.16 


A = -2187 


8.19 


| = .75 


30.20 


J = .25 


10.09 


1 - .875 


35.30 


A = .2812 


11.38 


1 = .1 


40.40 



Q. Explain how the above fractional parts 
of whole numbers are made to read as decimals 
— take T 3 g- of an inch for an example? 

A. To do this take 100 as a whole number; 
divide 16 into 100 = 6£, reads .625 == ^ of 
100. T \ would read, 3 X .625 = .1875. This 
principle answers for all the rest. 

Rule for safety valves. To find the distance 
ball should be placed on lever, when the weight 
is known, or the distance is known and weight 
is not known. Multiply the pressure required 
by area of valve, multiply the answer by the 
fulcrum; substract the weight of the lever^ 



— 87 — 

valve and stem, and divide by the weight of 
ball for distance, or divide by distance for 
weight of ball with the same example as fol- 
lows: 

EXAMPLE: 

Weight of ball, 60 lbs. 100 lbs. pressure. 

Pressure, 100 " __3 area of valve. 

Wt. of L. Y. & steam, 30 " 300 
Eulcrum, 4 inch , 4 fulcrum. 

Area of valve, 3 li 1200 

30 wt. of L. V, & st. 
60 )1170 

19£ inch ball should 
be hung on lever. 

The mean effective weight of valve, lever 
and stem is found by connecting the lever at 
fulcrum, tie the valve-stem to lever with a 
string, attach a spring scale to lever immedi. 
ately over valve, and raise until the valve is 
clear of its seat, which will give the mean effec- 
tive weight of lever, valve and stem. 

Rule for figuring the safety valve and to 
know the pressure when the area of valve, the 
weight of lever, valve and stem, the distance 
fulcrum is from valve, and weight of ball is 
known. 

Divide fulcrum into length of lever, multiply 



— 88 — 

answer by weight of ball, add weight of lever, 

valve and stem, and divide by area of valve. 

Answer will be steam pressure. 

Weight of ball, 50 lbs. 2.25 4)20 

Wt. of L. Y. and stem, 30 lbs. 2.25 5 

Fulcrum, 4 in. 5.0625 50 

Diam. of valve, 2i in. .7854 250 

Length of lever, 20 in. 3.97608750 area. 30 



Add as many ciphers to the divi- 3.9)280.0 



dend as there are decimels in the di- lbs.press. 71. || 
visor, and divide as whole numbers. 

To measure or mark off the lever, you 
measure the fulcrum and make notches the 
same distance as fulcrum; if fulcrum is 4 inches, 
each notch must be 4 inches apart. 

Q. What is meant by a fulcrum? 

A. The distance valve stem is from where 
the lever is connected. 



Rules for Machinists. 

Rule to Gear a Lathe for Screw-Cut- 
ting. — Every screw cutting lathe contains a 
long screw called the lead screw, which feeds 
the carriage of the lathe while cutting screws; 
upon the end of this screw is placed a gear to 
which is transmitted motion from another gear 
placed on the end of the spindle; these gears 
each contain a different number of teeth, for 
the purpose of cutting different threads, and 
the threads are cut a certain number to the 
inch, varying from one to fifty. Therefore, to 
find the proper gears to cut a certain number of 
threads to the inch, you will first multiply the 
number of threads you desire to cut to the inch 
by any small number, 4 for instance, and this 
will give you the proper gear to put on the lead 
screw. Then w r ith the same number, 4, multi- 
ply the number of threads to the inch in the 
lead screw, and this will give you the proper 

— 89 — 



— 90 — 

gear to put on the spindle. For example, if you 
want to cut 12 to the inch, multiply 12 by 4, and 
it will give you 48. Put this gear on the lead 
screw, then with the same number 4, multiply 
the number of threads to the inch in the lead 
screw. If it is 5, for instance, it will give you 
20; put this on the spindle and your lathe is 
geared. If the lead screw is 4, 5, 6, 7 or 8, the 
same rule holds good. Always multiply the 
number of threads to be cut first. 
Some — indeed, most small lathes — are now made 
with a stud geared into the spindle, which stud 
only runs half as fast as the spindle, and in 
finding the gears for these lathes you will first 
multiply the number of threads to be cut, as 
before, and then multiply the number of threads 
on the lead screw as double the number it is. 
For instance, if you want to cut 10 to the inch, 
multiply by 4, and you get 40; put this on the 
lead screw, then, if your lead screw is 5 to the 
inch, you call it 10, and multiply by 4, and it 
will give you 40. Put this on your stud and your 
lathe is geared, ready for cutting. 

Rule for Cutting a Screw in an Engine 



— 91 — 
Lathe. — In cutting V-thread screws, it is only- 
necessary for you to practice operating the 
shipper and slide s^rew-handle of your lathe 
before cutting* After having done this until 
you get the motions, you may set the point of 
the tool as high as the center^ and if you keep 
the tool sharp you will find no difficulty in cut- 
ting screws. You must, however, cut very 
light chips, mere scrapings in finishing, and 
must take it out of the lathe often, and look at 
it from both sides very carefully, to see that the 
threads do not lean like fish scales. After cut- 
ting, polish with a stick and some emery and oil. 
Rule for Cutting Square Thread 
Screws. — In cutting square thread screws, it 
is always necessary to get the depth required 
with a tool somewhat thinner than one-half the 
pitch of the thread, after doing this make 
another tool exactly the pitch of the thread 
and use it to finish with cutting a slight chip 
on each side of the groove. After doing this, 
polish with a pine stick and some emery. Square 
threads for strength should be cut one-half the 
depth of their pitch, while square threads for 



— 92 — 

wear may — and should be — cut three-fourths the 
depth of their pitch. 

Rule for Moxgrel Threads. — Mongrel, 
or half V half square threads, are usually made 
for great wear, and should be cut the depth of 
their pitch, and for extraordinary wear they 
may be cut 1^ the depth of the pitch. The 
point and the bottom of the grooves should be 
in width \ the depth of their pitch. What is 
meant here by the point of the thread is the 
outside surface, and the bottom of the groove 
is the groove between the threads. In cutting, 
these threads, it is proper to use a tool the 
shape of the thread, and in thickness about 
J- less than the thread is when finished. As it is 
impossible to cut the whole surface, at once, you 
will cut it in depth about y 1 ^ at a time then a chip 
off the sides of the thread, and continue in 
this way alternately till you have arrived at the 
depth required. Make a gauge of the size 
required between the threads and finish by 
scraping with water. It is usually best to 
leave such screws as these a little large until 
after they are cut, and then turn off a light 



— 93 — 
chip, to size them; this leaves them true and 
nice. 

Rule to Temper Tools Used Daily, Such 
as Chisels, Taps, Dies, Reamers, Twist 
Drills, Common Flat Drills, and Lathe 
Tools. — To temper flat, cape or side chisels, 
and common flat drills, put the tool to be tem- 
pered in the fire and heat slowly to a cherry red 
color, about 4 inches from the point. Then 
take it out and put it in the water, point first, 
about three or four inches, then draw it back 
quick about an inch from the point, and leave 
it so until the water will barely dry on the 
chisel, then take it out, polish it with a piece 
of sand stone, and let the heat that is left in 
the body of the tool force its way toward the 
point; it will be noticed immediately in the 
change of color. The color of temper for 
chisels to cut cast iron should be a dark straw, 
turning to a blue. The temper of chisels to 
cut wrought iron or steel should be plunged 
into water after the dark straw color has disap- 
peared affd the blue begins to show itself, and 
left in the water to cool off. In some cases, 



— 94 — 

where the tool is too cold and the temper will 
not draw, put the tool in and out of the fire 
often, until the temper shows itself, then cool 
immediately. If the temper gets to the point 
of tool before it is polished, it will have to be 
heated over again. The above rule answers 
for lathe, plainer and shaper tools as well. 

Taps, dies, reamers and twist drills should be 
tempered in oil. After being heated to a cherry- 
red all over equally, drop the tool into a bucket 
of oil (plumb) and leave it there until cold; 
then take it out and brighten it with emery- 
cloth; be careful not to drop it, because it is 
brittle and liable to break. To draw the tem- 
per of taps, reamers and twist drills, heat a 
heavy ring red hot and enter the tool centrally 
in the ring, so the heat will be equal from all 
sides. The hole in the ring should be about 
three times the diameter of the tool. An old 
pulley hub would be about right. The color 
for reamers, taps and twist drills should be 
dark straw, turning to a blue near the shank; 
where the color is changing too fast, drop a 
little water on it; after the right color is 



— 95 — 
obtained, cool off in water. To draw the tern- 
per in dies after being cooled in oil, set them 
(the threads up) on a piece of red-hot iron and 
draw temper the same color as taps. 

For tempering a spring, heat it cherry red 
and put it in oil; after it is cool, take it out 
and hold it over the fire until the oil burns off; 
then put the spring in the oil again, then in the 
fire; do this three times; after the last time, 
plunge it into water and cool off. 

A No O Why. A. Because steam is highly 
elastic and bulky, and, of itself, would have no 
effect in driving the hot water in any particular 
direction. But when steam is moving at a high 
velocity and is condensed these particles « of water 
have the power of driving the mam body before 
it into the boiler. 

The principal is easily explained, ^ instance. 
If a block of wood is laid upon the water it will 
float, but if it is thrown violently ^nward > 
will at first go below the surface. Then if there 
were something there to catch it and hold it we 
would have a state of affairs similar to the injec 
tor where the water enters the boiler by its own 
momlntum and is held there by the check valve. 



Adjustment and Setting of Corliss Engine Valves. 

It often happens that engineers, under whose 
control Coriiss engines are. placed, are not prac- 
tically acquainted with ths operation of the 
Corliss valve gear, and are at a loss what to 
do should the gear need adjustment. By care- 
fully observing the following questions and 
answers, the desired information will be found. 

Q. Into how many classes are the different 
types of Corliss valve gear divided? 

A. Into two general classes. 

Q. Which are they? 

A. To the first class belong the crab-claw 
gear, originnally used by George. H. Corliss, 
and later by Harris and other prominent Cor- 
liss engine builders. 

To the second class belong the half -moon 
valve gear, as used on the Reynolds Corliss 
engine built several years since, and followed 
in some recent designs of Corliss engines. 

— 96 — 



— 97 — 

Q. Which is the more favorable and widely 
known type now in general use? 

A. The half moon type. 

Q, Why so? 

A. Because the old style crab-claw steam 
valve opens toward the centre of the cylinder, 
which obstructs the supply passage and forces 
the steam to pass over and around the valves. 
This fault is overcome in the half moon type, as 
the steam valve opens away from the center of 
the cylinder, thus leaving a clear and direct 
passage for the steam into the cylinder. 

Q. Do the two different styles make any 
difference into the opening of the exhaust 
valves ? 

A. No. The difference in the two classes is 
simply in the direction of movement of steam 
valves; the exhaust valves open the same in 
either class, viz.: away from the center of the 
cylinder. 

Q. What name has the Corliss valve gear? 

A. It is called a detachable valve gear. 

Q. Why is it called detachable? 

A. Because the steaift yalves open positively 



— 98 — 

at the proper time by the direct action of the 
working parts of the engine, and continue to 
open until the connection with the working 
parts of the engine are broken by detaching or 
tripping the hook, by action of the cut-off cams. 

Q. How are the steam valves closed? 

A. When the steam valves are detached 
they are closed by the action of springs, weights, 
or more generally vacuum dash pots, thus cut- 
ting off the supply of steam. 

Q. How is the detachment or tripping de- 
termined? 

A. The time in the stroke at which the 
tripping takes place is known by the position of 
the cut-off cams, which are moved and controlled 
by the governor. 

Q. Does the cut-off cams trip the hook al- 
ways at the same point? 

A No. The cut-off is determined by the 
requirements of the load on the engine. 

Q. By what name is this cut-off known? 

A. The automatic cut-off. 

Q. How is the theory of the Corliss va^ 
motion easily understood? 



— 99 — 

A. The theory is easily understood by con- 
sidering the four valves as the four parts (or 
edges) of a common slide valve. 

Q. Why are the four valves of the Corliss 
engine considered as the four parts (or edges) 
of the common slide valve? 

A. The working edges of the two steam 
valves answering as the two steam edges of the 
slide valve, and the working edges of the two 
exhaust valves as the exhaust edges of the slide 
valve. 

Q. The Corliss having four valves, and the 
common slide valve only one, does it not make 
any difference in setting? 

A. As far as the setting the principle is the 
same; the only difference is in the adjustment. 

Q. Why does the adjustment make a differ- 
ence? 

A. The four working edges of the common 
slide valve are in one solid valve, so that any 
change or adjustment of one of the edges inter- 
feres with the other three. If one edge is to be 
changed in reference to the others, it must be 
done by altering the valve itself. The Corliss 



— 100 — 
valves, on the other hand, are adjustable, each 
by itself, and any one of the valves may be 
changed without disturbing the other three. 

Q. Can the adjustment be made while run- 
ning ? 

A. When the engineer is familiar with his 
engine and knows what changes are necessary, 
the adjustment may be, and is frequently, made 
without stopping the engine. 

Q. How many edges has a slide valve ? 

A. Four — two steam and two exhaust ♦ 

Q. Has the Corliss valves the same number 
of edges as the common slide valves? 

A. No. Each Corliss valve represents an 
edge of the common slide valve, viz. : two steam 
edges, two steam valves, two exhaust edges, 
two exhaust valves. 

Q. How are the valves connected to the ec- 
centric and worked on Corliss engines? 

A. With the wrist-plate, carrier arm, rocker 
arm and reach rod. 

Q. Is the wrist-plate good for any other pur- 
pose? 

A. Yes. It modifies the speed of travel at 



— 101 — 

different parts of the stroke, in relation to each 
other, and gives a quick and constantly increas- 
ing speed when opening the steam valves, and 
a quick opening and closing of the exhaust 
valves. 

Q. When do the steam and exhaust valves 
travel slowest? A. When they are closed. 

Q. Can the valves of Corliss engines be 
adjusted when the reach rod is unhooked from 
the wrist-plate, so the valves may be properly 
set, independent of the position of the crank? 

A. Yes. 

Q. Are the Corliss valves easily set? 

A. If the engineer has any knowledge, as he 
should have, of the ordinary slide valve, and of 
the effect of "lap and lead" as applied to its 
working, and will consider the Corliss valve 
gear in the light of this knowledge, he will soon 
master the seeming difficulties in his way and 
find the Corliss gear to be the simplest, most 
perfect and most easily adjusted of all valve 
motions. 

Q. How would you go about setting the 
Corliss valves? 



— 102 — 
A. Begin by taking off the back caps or back 
heads of all four valve chambers. Guide lines 
will be found on the ends of the valves and on 
the ends of the chambers, as follows: On the 
steam valves, coinciding with the working edges 
of the valves; on the steam valve chambers, co- 
inciding with the working edges of the steam 
ports. On the exhaust valves and ports, guide 
lines are also scribed to set them by. The wrist- 
plate is centrally between the four valve cham- 
bers, on the valve gear side of the cylinder. A 
well defined line will be found on the stand 
which is bolted to the cylinder, and three lines 
on the hub of the wrist-plate, which, when they 
coincide with the line on the stand, show the 
central position of the wrist-plate and the ex- 
tremes of its throw or travel. To adjust the 
valves, first unhook the reach rod connecting 
wrist-plate with rocker arm and place and hold 
the wrist-plate in its central position. The con- 
necting rods between steam and exhaust valve 
arms and wrist-plate are made with right and 
left hand screw threads on their opposite ends, 
and provided with jamb nuts, so that 1 y slack- 



— 103 — 

ing the jam! nuts and turning the rod they can 
be lengthened or shortened as desired. By- 
means of this adjustment, set the steam valves 
so that they will have \ inch lap for 10 inch 
diameter of cylinder, and -J inch lap for 32 inch 
diameter of cylinder, and for intermediate diam- 
eters in proportion. 

For the exhaust, set them with 1-16 inch lap 
for 10 inch bore, and -J- inch lap for 32 inch 
bore on non-condensing engines and nearly 
double this amount on condensing engines, for 
good results. Lap on the steam and exhaust 
valves will be shown by the lines on the valves 
being nearer the center of the cylinder than the 
lines on the valve chambers. Having made this 
adjustment of the valves, the rods connecting 
the steam valve arms with the dash pots should 
be adjusted by turning the wrist plate to its ex- 
tremes of travel and adjusting the rod so that 
when it is down as far as it will go, the sq. steel 
block on the valve arm will just clear the 
shoulder on the hook. If the rod is left too 
long, the steam valve stem will be likely to be 
either bent or broken; if too short, the hook will 



— 104 — 

not engage, and consequently the valve will not 
open. Having adjusted the valves as stated, 
hook the engine in and, with the eccentric loose 
on the shaft, turn it over and adjust the eccen- 
tric rod so that the wrist-plate will have the 
correct extremes of travel, as indicated by the 
lines on back of hub of wrist-plate. Then place 
the crank on either dead center and turn the 
eccentric in the direction in which the engine is 
to run to show an opening at the steam valve of 
from 1-32 to -J inch, depending upon the speed 
the engine is to run. This opening will be 
shown by the line on the valve being nearer the 
end of the cylinder than the line on the valve 
chamber. This opening gives the "lead" or 
port opening when the engine is on the dead 
center. The faster the engine is to run the 
more lead it requires, as a general rule. Having 
turned the eccentric so as to secure the desired 
amount of lead, tighten it securely, by means of 
the set screw, and turn the engine over to the 
other center, and note if the other steam valve 
has the same lead. If not, adjust by length- 
ening or shortening the connecting rod to the 



— 105 — 

wrist-plate as the case may be necessary to do. 

If the engine has the half -moon, crab claw, or 
other gear which opens the valves toward the 
center of the cylinder, the manner of the adjust- 
ment will be the same, except that the "lap" on 
the steam valves will be shown when the line 
on the steam valve is nearer the end of the cyl- 
inder, and the "lead" when this line is nearer 
the center of the cylinder than the line on the 
valve chamber. The adjustment of the exhaust 
valves and the amount of "lap" and "lead" will 
be the same in either case. 

To adjust the rods connecting the cut-off or 
tripping cams with the governor, have the gov- 
ernor at rest and the wrist-plate at one extreme 
of its travel. Then adjust the rod connecting 
with the cut-off cam on opposite steam valve so 
that the cam will clear the steel on the tail of 
the hook about ^ inch. Turn the wrist-plate 
to the opposite extreme of travel and adjust the 
cam for the other valve in the same manner. 
To equalize the cut-off and test its correctness, 
hook the engine in and block the governor up 
about 1J inch, which will bring it to its average 



— 106 — 

position when running. Then turn the engine 
slowly, in the direction in which it is to run, and 
note the distance the cross-head has traveled 
from its extreme position at dead center when 
the cut-off cam trips or detaches the steam valve. 
Continue to turn the engine beyond the other 
dead center and note the distance of cross-head 
from its extreme of travel when the valve drops. 
If the distance is the same as when the other 
valve dropped the cut-off is equal. If not, adjust 
either one or the other of the rods until the dis- 
tances are the same. 

By following these directions, the engine will 
do good work, but to know just what it is doing 
the engineer should use the indicator often. No 
engine room is complete without a good indi- 
cator, and no engineer can be well posted as to 
what his engine is doing and keep it in its best 
possible condition for good work without hav- 
ing an indicator and using it often. (See p. 68.) 



I 



THE DYNAMO. 

Q. What is a Dynamo? 

A. A Dynamo is a machine in which Elec- 
tricity is gathered and forced out through wires 
for lighting, Electro-plating, etc. 

Q. What does a Dynamo consist of? 

A. A Dynamo consists of a field, frame, arm- 
ature, commutator, brushes, brush holders, pins 
for the brush holders and a quadrant. 

Q. What is meant by a field ? 

A. It means the magnets connected to the 
frame with bolts. 

Q. What are magnets? 

A. Magnets are iron cores, wound with insu- 
lated wire. These magnets are called electro- 
magnets because they become magnetic only 
when a current passes through the wire. 

Q. How is the current generated? 

A. By the rotary motion of the armature 
between the poles of the magnet. 

Q. What does an armature consist of ? 

-107 — 



— 108 — 

A. It consists of either a steel or iron shaft, 
around which insulated wire is wound, the shaft 
having a 6 or 8 inch bearing at each end. 

Q. How is the current conducted to the 
lamps? 

A. By means of brushes made out of copper 
strips or wires about 6 or 8 inches long, sol- 
dered together at one end and held on the com- 
mutator by means of brush holders made out of 
brass. These holders are on long pins, the pins 
are nutted to a quadrant and the quadrant is 
fastened to the frame. 

Q. How many brushes are there generally, 
and where are they? 

A. There are 2 and 4 brushes, two on one 
side of the commutator and two directly oppo- 
site, according to size of machine. 

Q. What is a commutator? 

A. A commutator is made out of segments 
of copper and segments of insulation. 

Q. Can a commutator be taken off when 
worn out? A. Yes. 

Q. How is it generally done? 

A. By taking out the brushes, brush hold- 



—109 — 
ers, the pins and the armature from the dynamo, 
then place the two ends of the shaft on wooden 
horses, mark the wires connecting the armature 
and commutator by attaching numbered tags (so 
a8 to place them, when the new commutator is 
put on) then disconnect the wires between the 
commutator and armature and take off the .com- 
mutator from the shaft. ^ 

Q. How should a dynamo be looked after 

and run ? 

A. See that the machine is clean, journals 
cool, and that the proper speed is kept up; see 
that the brushes are directly opposite each other 
and that the quadrant and brushes are moved 
around on the commutatar according to the 
number of lights in use. 

Q. How would you know when to move the 

quadrant? 
A. By the sparking of the brushes on the 

commutator. 

Q. What mainly causes the dynamo to flash 

or spark ? 

A. The brushes not being directly opposite 
through the diameter of the commutator, some- 



— 110- 
times not enough pressure on the commutator, 
sometimes the brushes not far enough around on 
the commutator, also too much brush surface. 

Sparkling at the brushes. Some styles of 
dynamos will spark at the brushes in spite of 
anything the attendant can do to prevent it, but 
many other styles of dynamos can be run with 
absolutely no sparks on the commutator. The 
first point to be attended to is to get your com- 
mutator perfectly smooth, or as near it as possi- 
ble, with the means at your command, for if the 
commutator is not true you can not prevent it 
from sparking. 

If you have a slide-rest, use it, and get your 
commutator round and true from end to end. 
If you have no slide-rest, a 16 in. bastard file 
will do nearly as well. Take the brushes and 
brush holders off, so that you may have plenty 
of room to work. Start the dynamo to turning 
very slowly. Hold a piece of chalk so near the 
commutator that it will mark all of the high 
spots. Move the chalk slowly from end to end 
of the commutator, so that all high places on 
the full length will be chalked. Stop the 



— Ill — 

dynamo and amuse yourself filing oft those 
parts that have been marked by the chalk. If 
you have noticed while the dynamo was turning 
about how much the commutator was "out" 
you can easily tell about how much you wi 
have to file away to bring it true. File off all 
the places that have been marked, and then start 
up again slowly, and chalk it again. Repeat 
the chalking and filing until the commutator is 
round, and of the same size from end to end. 
Next get a piece of shingle, thin board, or a 
piece of lathe even will do, and wrap a sheet 
of No. oo. sand-paper around it-never use 
emery paper or cloth-start the dynamo at a 
pretty lively speed, and smooth the commuta- 
tor down with the sand-paper, holding the flat 
side against the work. It is not necessary to 
work it down to * polished surface, although it 
would be well if it were polished. Now that 
you have your commutator round and smooth- 
ed it must be so smooth that there are none 
of the marks left on the commutator, for it 
was trouble that caused them, and if any oe left 
they will certainly cause more trouble. 



— 112 — 

Now, that you know your commutator is in 
good shape, proceed to set your brushes, being 
certain that the points of opposite brushes are 
directly opposite through the diameter. The 
pressure put on the brushes need only be just 
sufficient to make good contact. It is not neces- 
sary to have much pressure to preserve good 
contact. Should the contact be too slight it will 
make itself known by a peculiar noise that is 
indescribable, being neither a snap, crack or pop, 
and yet might be called by either of these 
names. You may be sure that the noise will 
call your attention if you are anywhere near, 
and after you have once noticed it you will 
easily recognize it the next time. This noise 
and considerable sparking will always be 
present when the brushes do not press heavily 
enough upon the commutator. 

If the brushes are not set with the points 
directly opposite, sparking will result. 

If the brushes are set ahead of the neutral 
line or back of it they will spark. 

When setting four brushes on a commutator 
that requires two brushes side by side, it is 



— 113 — 

sometimes difficult to get all four of them of 
an equal length, or evenly divided on the com- 
mutator, one or more of them will spark more 
or less. After rocking the brushes back and 
forth a trifle to find the point of least sparking, 
you can then tell by the color of the spark 
whether the brush should be lengthened or 
shortened. When the spark is of a decidedly 
greenish color the brush is too short, but if the 
spark appears to spatter and shows a reddish 
hue, then you will find that the brush is too 
long, or it is so worn that there is too much of 
it in contact. By the way, you will find fully 
as much, if not more, trouble arising from 
having too much of the brush in contact, than 
from having too little. 

Cutting of Commutator ', scratching and eat- 
ing away of the segments, is mostly due to the 
brushes having too much surface in contact, and 
increase of pressure will wear away the com- 
mutator, and having too much of the face of 
the brush in contact will cause an edge of the 
segments to become eaten away, and if not at- 
tended to, they will, in a very short time, be- 



— 114 — 

come as rough and uneven as a corduroy road. 

With the thicker style of brushes we have 
never found it necessary, even when running at 
full load, to have more than one-third of the 
full end surface of the brush in contact with 
the commutator, and further, we have found that 
if we allowed the brush to become so worn that 
even one-half of the end surface bore on the 
segments it would cause sparking. 

To prevent filing the brushes every day 
(which would be wasteful), to keep them in 
the best of order, we found that they could, 
with great atvantage, be turned the other side 
up and allowed to wear in that way until the 
surface became to great. This resulted in get- 
ting more than twice the amount of work out 
of a brush than was possible by filing always 
from one side, or trimming the ends square as 
often as they became badly worn. If the com- 
mutator becomes very hot you will be quite 
sure to find that your brushes are badly worn. 

Flat spots on the commutator, frequently ex- 
plained by laying it to soft spots in the copper, 
we have always found to result from an entirely 



— 115 — 

different cause. When the marks have the ap- 
pearance of a blow from the pene of a hammer, 
it will generally be found to be caused by a 
loosely connected or badly soldered armature 
wire connection. A spot of this kind contin- 
ues to grow larger until the cause of it is 
removed and the commutator dressed down 
smooth. 

At the end of the segments a spark or stream 
of fire encircling the whole commutator will 
sometimes be noticed. 

This may be caused by an accumulation ol 
oil or copper-dust or dirt, that causes a short 
circuit, but it will generally be found that the 
insulation is charred or burned through at some 
place near where the spark is noticed, and if a 
careful examination of the armature wires are 
made you will find that a connection is loose or 
has very poor conductivity. Allowing the com- 
mutator to run hot will increase difficulties of 
this kind, 



The Principle of the Dynamo compared with the 
Steam Pump. 

We are often asked how can a dynamo be 
easily understood; the questions coming from 
engineers who have charge of electric lighting 
plants. 

The whole thing may be compared, in its 
principles, to the working of a steam pump 
forcing water through aline of pipe of the same 
extent as the line wires. The dynamo (or pump) 
forces electricity instead of water. So long as 
the dynamo or pump works continuously the 
pipes or wires are filled with a current of water, 
or electricity, flowing in one direction; in other 
words; a continuous current. Thus we may say: 
that a certain number of pounds steam pressure 
is required to overcome the friction of the water 
in the pipes, so that so many cubic feet or gal- 
lons of water shall be delivered per minute, 
equally true we can say, so many volts are re- 

— 116 — 



— in- 
quired to overcome the resistance of the wire, 
so that the current shall be delivered in so many 
amperes per minute. Hence, to simplify, we 
may say pounds of steam pressure = volts; the 
friction=resistance; the pipe=the wire; current 
=volume of water in motion, and amperes of 
electricity=gallons of water delivered at the 
end per minute. Every engineer knows that 
the larger the pipe the more gallons water per 
minute, and the less relative friction, so the 
larger the wire the more current can be carried 
and the less the resistance, relative to the num- 
ber amperes delivered. The same analogy holds 
good in the opposite, for the smaller the pipe 
or wire, the greater the friction, or resistance. 
Every engineer who uses a steam pump or an 
injector, knows that there is some point to 
which, if his pipes were reduced in size, nearly 
or quite all his power (steam pressure) would 
be absorbed in friction. So electrically, our 
voltage may be largely consumed or absorbed by 
too small a wire; in either case — either the water 
or the electricity — the result of the wbrk done 
is in both cases uniform and identical, viz.: A 



— 118 — 
continuous current, and is the current that has 
been generally used for the production of light 
and power. The other current, which is largely 
employed in the generation of electrical power 
viz.: the alternating current, differs essentially 
from that which we have described above, and 
infact our analogy to the working of a pump 
comes to an end. The current from an alter- 
nating dynamo, instead of flowing continuonsly 
and directly, is simply a vibratory movement, 
or a "back and forth flow." Here the suprem. 
acy of electricity as a power, or rather as a 
transmitter of power, comes in, for, returning to 
oue pump, should we at each alternate stroke 
of the pump reverse the direction of flow of the 
water, the entire power, or nearly all of it, 
would be absorbed by its weight, and tbe fric- 
tion in the pipes. But electricity boing without 
weight, there is of course no loss by reversing 
its flow; indeed^ the possibilities of application 
to useful service, dependent on the reversals, 
are of the greatest value. To clearly explain 
the action of the alternating system, we have to 
consider the requirements under which elec- 



— 119 — 

tricity does its most acceptable work. 

Every engineer who is making electric lights 
knows that the most satisfactory results, L e., 
the best light, is obtained by using a dynamo 
and distributing system of as high voltage as 
possible, in conjunction with a lamp of low 
voltage. Here, then, we have two actually op- 
posite conditions, which must be harmonized to 
produce a perfect result in their action, and 
which are plainly impossible in the continuous 
current system, which we have explained by 
the comparison to our pump; because it is evi- 
dent, to renew the comparison; that if we are 
carrying a pressure (steam), and our line of 
pipes is calculated to deliver a certain amount 
of water per minute, if we throttle down at the 
delivery end, so as to deliver only -f$ or ^ of 
the amount, we shall only be able to do so by 
reducing our pressure relatively, involving a 
great loss of efficiency, or incur the risk of 
destruction to the plant at some point. 

Hence we are obliged to provide some appli- 
ance which shall intervene to convert the high 
voltage of the dynamo and circuit to the low 



— 120 — 

voltage of the lamps. When such an appliance/ 
is used it is known as a converter system, and 
the use of an alternating current and converter 
system are mutually dependent on and necessary 
to each other. 

This system can be compared to the en- 
gineer's system of steam heating in his build- 
ing thus: Suppose he carries 75 lbs. boiler 
pressure, and the steam is carried into the build- 
ing in one main pipe, and from that is dis- 
tributed by risers, etc., to the different radiators 
in the building. It is evident that he has no 
use for full boiler pressure on the risers and 
radiators, as, even if they would stand it for a 
time, it would be no more effective for heating 
than a reduced pressure; hence he puts in a 
reducing valve in the steam main, between the 
boilers and risers. 

So, then, the converter used in connection 
with an alternating current is exactly an elec- 
trical reducing valve, with a high pressure (vol- 
tage) on one side, and a low working pressure 
(voltage) on the other. Thus, by using this 
converter he may carry any voltage at the 



— 121 — 

dynamo and primary circuit, reducing into the 
secondary, to conform to the amount of current 
required. Each current continuous or alternate, 
have especial fields to which they are adapted, 
and while both are extensively in use each has 
its peculiar adaptation. 

Q. How do you understand the term "volt?" 
A. The "volt" is a measure of electro — 
motive force, or original energy. Corresponding 
to the dynamic term "pressure," but not of 
"power." It is based on the product of one 
Daniell cell of a battery. 

Q. How do you understand the term "ohm?" 
A. The "ohm" is the measure of resistance, 
and compares to the dynamic term of "loss by 
transmission." It is based on the resistence 
offered by a copper wire .05 in. diameter, 250 
ft. long; or a copper wire, 32 gauge, 10 ft. long. 
Q. How do you understand the term 
"ampere?" 

A. The" ampere," is the measure for current 
or what passes; the intensity, it may be called, 
and is comparable to the dynamic term of 
"power transmitted," or "effect." It is the res- 



— 122 — 

idual force of one "volt" after passing through 
one "ohm" of resistance. 

Q. How do you understand the term "cou- 
lomb?" 

A. The "coulomb" is a measure of current, 
qualified by time; one ampere acting for one 
second of time, comparing in nature with the 
dynamic "foot-pound." 

Q. How do you understand the term "watt?" 

A. The "watt" is the unit for dynamic effect 
produced by electro-motive force or current. It 
equals 44.22 foot-pounds, or one 746 h. p. 

Q How many "coulombs" in a "watt?" 

A. There are 44.22 "coulombs." 

Q. How many "watts" in an electrical h. p. ? 

A. There are 746 "watts" in a h. p. 

Q. How many horse power will it take to 
run a 50 arc light dynamo. Each arc light 
equaling 45 "volts" and 8 "amperes" giving 
1600 candle power to each light? 

A. Multiply the "voltage" by the "amperes" 
then the number of lights lit, and divide by 
electrical h. p. which is 746 "watts." The an- 
swer will be the h. p. of engine required. 



Receipts for Gold and: Silver Plating. 

Take a tablespoonful Cyanide of Gold and 
put it in a glass of water, to do gold plating. 



All articles to be plated should be dipped in 
strong lye or diluted nitric acid, and rinsed 
off with soft water; then place the article to be 
plated in the glass that has the solution of 
either gold or silver^ and take a couple of pieces 
of zinc 1 inch wide, and double to ^ in. wide, 
by 10 long, let it touch the article to be plated, 
and you will be surprised at the result. This 
answers for both. 

To make solution of silver for plating: — Take 
silver and dissolve in a glass with little nitric 
acid, when the silver is dissolved then drop hy- 
droloric acid in until the white precipitates, 
(silver chloride) ceases to fall, pour off the col- 
ored water after it has settled, and add soft 
water to it, then it is ready for use. 

— 123 — 



POINTS FOR ENGINEERS. 

Steam-Pipes, whether for power or for heat- 
ing, should always pitch downward from the 
boiler, that the condensed water, etc., may 
have the same direction as the steam, or other- 
wise there will be trouble, unless the pipes are 
either very short or very large. 

Globe valves should always be so placed in 
steam-pipes that their stems are very nearly 
horizontal, in order to prevent a heavy accumu- 
lation of condensed water in the pipes. Where- 
ever a horizontal steam-pipe is reduced in size 
there should be a drip to avoid filling the 
larger pipe partially with condensed water. 



In order to make a riist joint that will stand 
heat and cold as well as rough usage, mix ten 
(10) parts of iron filings and three (3) parts 
of chloride of lime with enough water to make 
a paste. Put the mixture on the joint and 
bolt firmly; in twelve hours it will be set so 
that the iron will break sooner than the cement. 

— 124 — 



Rules for Calculating Speed and Sizes of Pulleys. 

To find the size of driving pulley. 

Multiply the diameter of the driven by the 
number of revolutions it shall make, and divide 
the answer by the revolutions of the driver per 
minute. The answer will be the diameter of 
the driver. 

To find the diameter of the driven that shall 
make a given number of revolutions: 

Multiply the diameter of the driver by its 
number of revolutions, and divide the answer 
by the number of revolutions of the driven. 
The answer will be the diameter of the driven. 

To find the number of revolutions of the 
driven pulley: 

Multiply the diameter of the driver by its 
number of revolutions, and divide by the diam- 
eter of the driven. The answer will be the 

number of revolutions or the driven. 
125 



Table of Diameters and Cm 

CTTMFERENCES OF ClRCL.ES. 



Table Showing the Areas 
of the Diameters of Cir- 
cles and Areas of Ci rcles 



Dia. 


Cir. 


% 


.3927 


X 


.7854 


V* 


1.578 


% 


1.963 


% 


2.741 


1 


3.142 


H 


4.712 


2 


6.283 


X A 


7.854 


3 


9.425 


4 


12.56 


5 


15.71 


6 


18.85 


7 


21.99 


8 


25.13 


9 


28.27 


10 


31.41 


11 


34.55 


12 


37.70 


13 


40.84 


14 


43.98 


15 


47.12 


16 


50.26 


17 


53.40 


18 


56.55 


19 


59 69 


20 


62.83 


21 


65.97 


22 


69.11 


23 


72.25 


24 


75.40 


25 


78.54 


23 


81.68 


27 


84.82 


28 


87 96 


29 


91.10 


30 


94.25 


31 


97.39 


32 


100.5 


33 


103.6 


34 


106.8 


35 


109.9 


36 


113.1 


37 


116.2 



38 
39 
40 
41 
42 
43 
44 
45 
46 
47 
48 
49 
50 
51 
52 
53 
54 
55 
56 
57 
58 
59 
60 
61 
62 
63 
64 
65 
66 
67 
68 
69 
70 
71 
72 
73 
74 
75 
76 
7V 
78 
79 
80 
81 



119.4 
122.5 
125.6 

128.8 
131.9 
135.1 
138.2 
141.4 
144.5 
147.6 
150.8 
153.9 
157.1 
160.2 
163.3 
166.5 
169.6 
172.8 
175.9 
179.1 
182.2 
185.3 
188.5 
191.6 
194.8 
197.9 
201.0 
204.2 
207.3 
210.5 
213.6 
216.7 
219.9 
223.0 
226.2 
229.3 
232.5 
235.6 
238.7 
241.9 
245.0 
24«.2 
251.3 
254.5 



0. 
0j 



0. 


1 

3. 

4 
7, 

12. 

19. 

28. 

38. 

50. 

63. 

78, 

95. 
113. 
132. 
153. 
176. 
201. 
226 
254. 
283. 
314. 
346 
380. 
415. 
452, 
490, 
530, 
572, 
615. 
660, 
706 
754 
804 
855, 
90' 



0123 
,0491 
1963 

3068 

6013 

7854 

762 

142 

,909 

OoS 

,566 

635 

274 

484 

,265 

617 

54 

03 

10 

73 

94 

71 

06 

98 

47 

53 

16 

.36 

13 

,48 

,39 

,87 

,93 

.56 

75 

52 

.86 

.77 

25 

,30 

.92 

.11 



1017.9 

37 11075.2' 



Size. 


Area. 


38 


1134.1 


39 


1194.6 


40 


1256.6 


41 


1320.2 


42 


1385.4 


43 


1452.2 


44 


1520.5 


45 


1590.4 


46 


1661.9 


47 


1734.9 


48 


1809.6 


49 


1885.7 


50 


1963.5 


51 


2042.8 


52 


2123.7 


53 


2206.2 


54 


2290.2 


55 


2375.8 


56 


2463.0 


57 


2551.8 


58 


2642.1 


59 


2734.0 


60 


2827.4 


61 


2922.5 


62 


3019.1 


63 


3117.2 


64 


3217.0 


65 


3318.3 


66 


3421.2 


67 


3525.7 


68 


3631.7 


69 


3739.3 


70 


3848.5 


71 


8959.2 


72 


4071.5 


73 


4185.4 


74 


4300.8 


75 


4417.9 


76 


4536.5 


77 


4656.7 


78 


4778.4 


79 


4901.7 


80 


5026.6 


81 


5153.0 



To find the Circum. of any 
Cir. see page 74. 



To find the Area of any Circle 
or diameter see page 74. ^ 



-126- 



INDEX. 



Preface 3 

The Boiler in General 5 

Pump s 27 

TheEngine 39 

How to Line an Engine 47 

Valve Motion 58 

The Indicator 68 

BULES. 

For Finding H. P. of Engine, with Example. . 67 

To Figure a Diagram 73 

For Finding Friction 73 

Standard Multipliers, with examples 74 

For Finding Contents of Boiler 75 

For Finding Pressure on Crown Sheet 75 

For Finding Quantity of Water and Coal Used 

per Horse Power .... 76 

For Finding Contents of a Tank 77-78 

For Marking Tools, 78 

For Chimneys 78 

For Babbitting Boxes and making Babbitt. . . . 79 

To Determine Capacity of any Pump 80 

For Safe Working Pressure of Boiler 80-81 

— 137 — 



— 128 — 

For Finding Pressure Strains of Boilers 81-82 

For Heating Buildings 82-83 

For Finding Horse Power of Boiler 83-84-85 

For Finding Weight of Square Superficial Foot 
of Boiler Plate when Thicknes s is known . 86 

For Safety Valves 86-87-88 

For Machinists 89 

For Figuring the Gears to Put on a Lathe 89 

For Tempering Tools Used Daily 93 

For Tempering Springs 95 

Adjustment and Setting of Corliss Engine 

Valves 96 

The Dynamo with Example 107-122 

The Different Terms Used in Electricity. . . .121-122 

For Figuring H. P. of Dynamo 122 

For Gold and Silver Plating 123 

For Points for Engineers 124 

For Calculating Speed and Size of Pulleys 125 

Areas of Circles 126 

For Explaining the Injector 46 

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here. Books must be flexible, black, alligator, 
leatherette binding; red edge and roundcorners. 

Send money in registered letter or postoffice 

order only. Price 

P. H. ZWICKER, 

1607 Wash, Street, St, Louis* Mo. 

AGENTS WANTED, 



